INTERNATIONAL CIVIL AVIATION ORGANIZATION · 2012-01-09 · INTERNATIONAL CIVIL AVIATION ORGANIZATION. ... That, the WAFS-related regi onal procedures in all basic ANPs/FASIDs as

WAFSOPSG/2-REPORT

SECOND MEETING

OF THE WORLD AREA FORECAST SYSTEM OPERATIONS GROUP (WAFSOPSG/2)

(Bangkok, Thailand 8 to 11 March 2005)

INTERNATIONAL CIVIL AVIATION ORGANIZATION

The designation and the presentation of material in this publication do not imply the expression of anyopinion whatsoever on the part of ICAO concerning the legal status of any country, territory, city or areaof its authorities, or concerning the delimitation of its frontiers or boundaries.

History of the Meeting i-1

TABLE OF CONTENTSPage

List of WAFSOPSG decisions and conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Agenda Item 1: Opening of the meeting

Place and duration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Attendance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Chairman and officers of the Secretariat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Agenda Item 2: Organizational matters

Adoption of working arrangements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Adoption of the agenda . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Agenda Item 3: Follow-up of WAFSOPSG/1 conclusions

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Detailed follow-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Agenda Item 4: Review of ICAO provisions related to WAFS

Review of the ANP FASID procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Review of draft Amendment 74 to Annex 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Agenda Item 5: Operation of the WAFS

WAFS management report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Update of the back-up procedures in the WAFCs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2

Harmonization of the output of WAFCs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3

Development of WAFS output performance indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6

Availability of WAFS forecasts in chart form beyond 1 July 2005 . . . . . . . . . . . . . . . . . . . . . 5-7

Agenda Item 6: Development of the WAFS

Requirements for additional maximum wind levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1

Development of quantitative airframe icing intensity criteria . . . . . . . . . . . . . . . . . . . . . . . . . 6-2

Development of improved WAFS output products for icing and turbulence . . . . . . . . . . . . . . 6-3

Feasibility of amending the lead time for issuance of SIGWX forecasts . . . . . . . . . . . . . . . . 6-4

i-2 WAFSOPSG/2

Future requirements for WAFS SWM forecasts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5

Migration to the GR1B2 code form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5

Quality control of MET information in the ADS messages . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6

Depiction of aerodromes on SIGWX charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7

Agenda Item 7: Future work programme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1

Agenda Item 8: Any other business

SADIS seminar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1

WAFSOPSG/3 Meeting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2

Liability of WAFC Provider States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2

Joining two WAFC charts of different fixed time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2

Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2

Appendix A — List of participants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

Appendix B — ANP/FASID provisions related to WAFS . . . . . . . . . . . . . . . . . . . . . . . . . B-1

Appendix C — Draft amendment to Annex 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1

Appendix D — Draft amendment to Annex 3 concerning the deletion of back-upprocedures at the WAFCs in Attachment C . . . . . . . . . . . . . . . . . . . . . . . .

D-1

Appendix E — Draft amendment to Annex 3 concerning the prioritisation of plottingvolcanoes, tropical cyclones and radiation symbols on WAFS SIGWXcharts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

E-1

Appendix F — Proposed description for output products for turbulence, icing andCB/TCU clouds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

F-1

Appendix G — Draft amendment to Annex 3 concerning the lead time of issuance ofSIGWX forecasts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

G-1

Appendix H — Work programme of the WAFSOPSG . . . . . . . . . . . . . . . . . . . . . . . . . . . . H-1


LIST OF WAFSOPSG DECISIONS

Decision 2/1 — Follow-up of the WAFSOPSG/1 conclusions . . . . . . . . . . . . . . . . . . . . . . . 3-1

Decision 2/19 — Future of the SWM forecasts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5

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LIST OF WAFSOPSG CONCLUSIONS

Conclusion 2/2 — Amendment to WAFS-related regional procedures in the ANP/FASID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Conclusion 2/3 — Draft amendment to Annex 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Conclusion 2/4 — Development of a tracking system displaying the status ofimplementing changes to the WAFS . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Conclusion 2/5 — Development of the ISCS User Guide . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2

Conclusion 2/6 — Draft amendment to Annex 3 concerning the deletion of back-upproceduresat the WAFCs in Attachment C . . . . . . . . . . . . . . . . . . . . . . . 5-2

Conclusion 2/7 — WAFC London back-up services to support ISCS . . . . . . . . . . . . . . . . . 5-3

Conclusion 2/8 — Depiction of the vertical depth of the jetstream . . . . . . . . . . . . . . . . . . . 5-4

Conclusion 2/9 — Automatic production of WAFS SIGWX charts from the BUFR code . 5-5

Conclusion 2/10 — Draft amendment to Annex 3 concerning the prioritisation of plottingvolcanoes, tropical cyclones and radiation symbols on WAFS SIGWXcharts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5-5

Conclusion 2/11 — WAFS output performance indicators . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6

Conclusion 2/12 — Extension of the provision of SIGWX forecasts in chart form beyond1 July 2005 for a limited period of time by WAFC London andWashington . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8

Conclusion 2/13 — Availability of WAFS SIGWX forecasts in chart form using the PNGformat or an equivalent industry standard . . . . . . . . . . . . . . . . . . . . . . . . 5-9

Conclusion 2/14 — Improvements in the temporal and spatial resolution of WAFSupperwind forecasts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2

Conclusion 2/15 — Development of an objective icing index . . . . . . . . . . . . . . . . . . . . . . . . 6-2

Conclusion 2/16 — Development of improved forecasts for icing, turbulence and CB/TCUin the grid point format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3

Conclusion 2/17 — Draft amendment to Annex 3 concerning the lead time of issuance ofSIGWX forecasts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4

Conclusion 2/18 — Advancing the lead time of issuance of SIGWX forecasts . . . . . . . . . . 6-4

Conclusion 2/20 — Migration to the GRIB2 code form . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6

Conclusion 2/21 — Quality control of the MET information data block of the ADSmessages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7

Conclusion 2/22 — Amendment to the Guidelines for presenting WAFS SIGWX data inBUFR concerning the depiction of aerodrome on SIGWX charts . . . . . 6-7


Conclusion 2/23 — Update of the work programme of the WAFSOPSG . . . . . . . . . . . . . . . 7-1

Conclusion 2/24 — International SADIS seminar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1

— — — — — — — —

Report on Agenda Item 1 1-1


1.1 Place and duration

1.1.1 The second meeting of the WAFS Operations Group (WAFSOPSG) was held in the Asia/Pacific (ASIA/PAC) Regional Office, Bangkok, 8 to 11 March 2005.

1.1.2 The meeting was opened at 0900 hours by Mr. S. Ali, Deputy Regional Director, ICAOASIA/PAC Regional Office, who gave an overview of the activities of the regional office, and highlightedthe main tasks of the group and its role in ensuring that the world area forecast system (WAFS) continuedto meet evolving global and, where appropriate, regional operational requirements.

1.2 Attendance

1.2.1 The list of participants is given in Appendix A.

1.3 Chairman and officers of the Secretariat

1.3.1 The Chairman of the group, Mr. D. Visoiu (Romania), presided over the meeting throughoutits duration.

1.3.2 Dr. O. M. Turpeinen, from ICAO Headquarters, Montreal, was secretary of the meeting,assisted by Mr. D. Ivanov, Regional Officer, Meteorology, Bangkok.

— — — — — — — —



2.1 Adoption of working arrangements

2.1.1 The meeting adopted appropriate working arrangements.

2.2 Adoption of the agenda

2.2.1 The following agenda was adopted:



2.1 Adoption of working arrangements

2.2 Adoption of the agenda

Agenda Item 3: Follow-up of WAFSOPSG/1 Conclusions


4.1 Review of ANP/FASID procedures

4.2 Review of draft Amendment 74 to Annex 3


5.1 WAFS management report

5.2 Update of the back-up procedures at the WAFCs

5.3 Harmonization of the output of WAFCs

5.4 Development of WAFS output performance indicators

5.5 Availability of WAFS forecasts in chart form beyond 1 July 2005


6.1 Requirements for additional maximum wind levels

6.2 Development of quantitative airframe icing intensity criteria

6.3 Development of improved WAFS output products for icing and turbulence

6.4 Feasibility of amending the lead time for issuance of SIGWX forecasts

2-2 WAFSOPSG/2

6.5 Future requirements for WAFS SWM forecasts

6.6 Migration to the GRIB2 code form

6.7 Quality control of MET information in the ADS messages

Agenda Item 7: Future work programme


— — — — — — — —


Agenda Item 3: Follow-up of WAFSOPSG/1 conclusions

3.1 Introduction

3.1.1 The group recalled that the WAFSOPSG/1 Meeting formulated twenty-five conclusions andfive decisions. No follow-up action was required on decisions; therefore, they are not addressed in this paper.

3.2 Detailed follow-up

3.2.1 The group noted that action had been completed on all the issues except for Conclusion 1/13(action from the IATA Member of the group expected), and Conclusions 1/15 and 1/27 (action from theWAFC Provider States expected). Therefore, the group agreed that these conclusions should be restatedunder the relevant sub-items of Agenda Item 6.

3.2.2 The group formulated the following decision:

Decision 2/1 — Follow-up of the WAFSOPSG/1 conclusions

That, the follow-up action on the WAFSOPSG/1 conclusions be consideredcompleted except for Conclusions 1/13, 1/15 and 1/27.

Note.— Conclusions 1/13, 1/15 and 1/27 are restated under AgendaItem 6.

— — — — — — — —



4.1 Review of the ANP/FASID procedures

4.1.1 The group recalled that it was tasked to review the regional procedures contained in theANP/FASID at every meeting.

4.1.2 The group reviewed the regional procedures and proposed amendments, which would renderthem compatible with Annex 3 provisions. Accordingly, the update would eliminate the requirement forupper wind and upper-air temperature forecasts in chart form. The provision of significant weather (SIGWX)forecasts in chart form would, however, be continued beyond the date (i.e. 1 July 2005) stated in Annex 3,in response to APANPIRG Conclusion 15/32 and EANPG Conclusion 46/24 which had called for a limitedextension of the availability of WAFS SIGWX forecasts in chart form (paragraph 5.5 refers). The group alsoagreed that, whilst requirements for SIGWX forecasts in the BUFR code form no longer existed for flightlevels above FL 450, the upper limit of these forecasts should nevertheless remain at FL 630 for two reasons:a) any change to the upper limit would impact the BUFR encoding/decoding software and could be costlyfor WAFS Provider States and users; and b) the information related to the layers above FL 450 could continueto be provided by the WAFC Provider States with no significant operational/cost implications.

4.1.3 The group formulated the following conclusion:

Conclusion 2/2 — Amendment to WAFS-related regional procedures inthe ANP/FASID

That, the WAFS-related regional procedures in all basic ANPs/FASIDs as shownin Appendix B to this report be referred to the ICAO Regional Offices concernedfor processing and onward transmission to States for comments, as necessary.

4.2 Review of draft Amendment 74 to Annex 3

4.2.1 The group was aware that, at its first meeting, it had formulated the following conclusionswhich called for the Secretariat to prepare draft amendments to Annex 3:

a) Conclusion 1/1 — Revision of Chapter 9 and Appendix 8 of Annex 3;

b) Conclusion 1/19 — Elimination of clouds other than CB and TCU from the medium-level SIGWX forecasts

c) Conclusion 1/21 — WAFS charts for standard ICAO areas of coverage

d) Conclusion 1/22 — Depiction of meteorological and other features on WAFS forecastcharts

e) Conclusion 1/25 — Amendments to SIGWX forecasts; and

f) Conclusion 1/28 — Introduction of forecasts of height above ground level of thestandard WAFS flight levels.

4-2 WAFSOPSG/2

It was noted that no amendment had been prepared in response to WAFSOPSG Conclusion 1/26 — Futureof the SWM forecasts, since the underlying study by the WAFC Provider States had not yet been completed.

4.2.2 The Secretariat, in close coordination with WMO, had developed a draft amendment toAnnex 3, which was welcomed by the group; this amendment would simplify the provisions and wastherefore expected to improve the readability of Annex 3.

4.2.3 The group agreed that references to the amendments to the WAFS SIGWX forecasts shouldbe removed from Annex 3 in accordance with WAFSOPSG Conclusion 1/25 but was informed by WAFCLondon that they reserved the option of issuing amendments to WAFS SIGWX forecasts by a text message(FXUK 65/66 EGRR).

4.2.4 The group reviewed the draft amendment. It was realized that the amendment went beyondthe issues being customarily dealt with by the group since the action called for by WAFSOPSGConclusion 1/1 necessitated a thorough and complete revision of Chapter 9 and Appendix 8 of Annex 3.During the review, the group agreed that, in order to improve the internal consistency of Annex 3, the term“altitude”, in lieu of “height”, should be used in accordance with the definitions included in Chapter 1 ofAnnex 3 wherever the reference level was the mean sea level. The group also agreed to the proposal to deletethe provision related to the issuance of provisional TAF in view of substantial improvements achieved overthe last few years in the availability of OPMET data. However, considering the importance of this change,the group felt that this particular deletion should be brought to the attention of Contracting States during theconsultation process.


RSPP Conclusion 2/3 — Amendment to Annex 3

That the proposal to amend Annex 3 — Meteorological Service for InternationalAir Navigation given in Appendix C to this report be included as part ofAmendment 74 to Annex 3.

Note.— The deletion of provisional TAF should be brought tothe attention of Contracting States during the consultation process.

— — — — — — — —



5.1 WAFS management report

5.1.1 The group noted that a WAFS management report had been prepared by the WAFC Londonand WAFC Washington Provider States, in response to action called for by Conclusion 1/3, and that itcontained an executive summary, an assessment of the performance of WAFS (showing a high reliability asfar as the availability and timeliness of the forecasts were concerned), a description of significant changesto the WAFS, an overview of back-up procedures, an account of developments of the system, and a list ofspecific issues affecting the WAFS. The group reviewed the management report, noted its content andexpressed satisfaction with the scope of information provided; the report was considered to cover all theissues called for by Conclusion 1/3.

5.1.2 The group also recalled that it had invited the WAFC Provider States to develop adequatenotification procedures for significant changes to the WAFS operation (Conclusion 1/6). This issue was dealtwith in the management report by a proposal which would establish a tracking system for the status of theimplementation of changes to the WAFS, to be implemented by the WAFC Provider States. The groupconcurred to the establishment of a tracking system and agreed that such a system would address the concernsraised by the group in Conclusion 1/6. It formulated the following conclusion:

Conclusion 2/4 — Development of a tracking system displaying thestatus of implementing changes to the WAFS

That, the WAFC Provider States be invited to develop a tracking system, forinclusion in the WAFSOPSG website by the WAFSOPSG/3 Meeting, showingthe status of the implementation of changes made by the WAFCs which mayinfluence the operation of the WAFS.

Note.— The tracking system should include the following items to beprovided by the WAFC Provider States:

a) a summary of change;

b) impact on end users (including the minimum actions required);

c) assessment on the scope of the change (i.e. major, intermediate orminor),

d) implementation schedule; and

e) up-to-date comments on the current status of implementation.

5.1.3 It was noted that a related issue concerning the provision of information to States and WAFSusers concerning the WAFS in general, and the ISCS broadcast in particular, had been raised by the 12th

Meeting of the GREPECAS, which had formulated Conclusion 12/55 calling for the WAFSOPSG to studythe possibility of developing an ISCS User Guide. The group was aware that such a guide, the SADIS User

5-2 WAFSOPSG/2

Guide, concerning the SADIS broadcast had been developed by the SADISOPSG, based on input from theSADIS Provider State, and that this user guide was highly valued by all SADIS users. Therefore, the groupagreed that WAFC Washington be invited to develop a similar guide, in time for the WAFSOPSG/3 Meeting,and formulated the following conclusion:

Conclusion 2/5 — Development of the ISCS User Guide

That, WAFC Washington, in coordination with the ICAO Secretariat, be invitedto develop an ISCS User Guide with a scope similar to that covered by theSADIS User Guide.

Note.— There is no need to develop Annex 1 entitled “OPMET informationrequired from aerodromes to be included on the ISCS broadcast”, nor Annex 4entitled “WAFS forecasts disseminated on the ISCS” since OPMET and WAFSdata required to be included in the ISCS are identical to that included in SADIS.

5.2 Update of the back-up procedures at the WAFCs

5.2.1 The group was aware of the fact that guidance on back-up procedures at the WAFCs had beeninitially developed for the MET Divisional Meeting (2002) and included in Annex 3, Attachment C, as partof Amendment 73. At the WAFSOPSG/1, it was realized that the back-up procedures had to be updated toreflect some recent changes. To provide WAFS users with the most up-to-date information on back-upprocedures, it had been agreed that they should be placed on the WAFSOPSG website (Conclusion 1/9refers). It had also been agreed that the back-up procedures should be reviewed at the WAFSOPSG/2Meeting.

5.2.2 The group undertook the review of the back-up procedures and agreed that no changes wererequired. However, it was expected that some amendments would become necessary over the next fewmonths and that these amendments would be presented to the WAFSOPSG/3 Meeting for review. In viewof the dynamic nature of the back-up procedures, the group considered that the three-year amendment cycleinvolved in any Annex 3 amendment was too infrequent as far as the back-up procedures were concerned.As it would be undesirable to display two conflicting versions (i.e. one outdated in Attachment C to Annex3 and another up-to-date version on the WAFSOPSG website) to WAFS users, the group agreed thatAttachment C to Annex 3 should be deleted and that only a reference to the WAFSOPSG website containingthe up-to-date back-up procedures should be retained in Annex 3. The group formulated the followingconclusion:

RSPP Conclusion 2/6 — Amendment to Annex 3 concerning the deletion ofback-up procedures at the WAFCs in Attachment C

That the proposal to amend Annex 3 — Meteorological Service for InternationalAir Navigation concerning the deletion of back-up procedures at the WAFCsgiven in Appendix D to this report be included as part of Amendment 74 toAnnex 3.

5.2.3 The group addressed an additional proposal made by WAFC London related to the back-upprocedures, i.e. the establishment at WAFC London of a bulletin monitoring facility that could be used to


verify, on a real-time basis, the operation of the ISCS broadcast. If such a function were established, aworkstation would need to be procured and a modest amount of operator resource would need to be utilised.

5.2.4 The group concurred that WAFC London should be tasked to monitor the ISCS broadcastin order to be able to provide an effective back-up service to the ISCS broadcast, when necessary. It wasunderstood that the WAFC Washington Provider State already monitored the ISCS broadcast at least twodifferent sites. Nevertheless, the establishment of a monitoring function of the ISCS broadcast by WAFCLondon was considered warranted in view of its back-up responsibilities. In this regard, the group formulatedthe following conclusion:

Conclusion 2/7 — WAFC London back-up services to support ISCS

That, WAFC London be invited to:

a) continue to provide a back-up data service to the ISCS uplink hub andmaintain reception capability of the ISCS broadcast; and

b) establish a bulletin monitoring facility that could be used to verify, on areal-time basis, the operation of the ISCS broadcast.

5.3 Harmonization of the output of WAFCs

5.3.1 Under this sub-item, three issues were addressed:

a) the vertical “depth” of the jetstream;

b) enhancement of the Guidelines for representing WAFS SIGWX data in BUFR for thesoftware to automatically produce compliant SIGWX charts from the BUFR code for thestandard ICAO areas; and

c) prioritisation of plotting volcanoes, tropical cyclones, and radiation symbols on WAFSSIGWX charts.

5.3.2 With regard to the depth of the jetstream, the group recalled that a new model chart SWHhad been developed for consideration by the MET Divisional Meeting (2002) and included in Appendix 1to Annex 3, as part of Amendment 73 to Annex 3. As a result of this amendment, Appendix 1 to Annex 3contained three SWH model charts; two of these charts (Examples 1 and 2) did not include any informationon the vertical depth of jetstreams while the third one (Example 3) displayed jet depths against every heightindication. Since, in accordance with the Working Arrangements between ICAO and WMO (Doc 7475), themodel charts and forms were the responsibility of WMO, the group agreed that WMO should be invited toeliminate this discrepancy by deleting the model charts with no jet depth information. Furthermore, in orderto avoid clutter and improve the legibility of the charts, it was suggested that WMO should consider includingonly one jet depth information group per jetstream on the model chart. This proposal appeared to be justifiedin light of advice provided by the WAFC Provider States which indicated that the inclusion of the jet depthinformation for each point on the jet stream would add some 30 to 45 minutes to the typical production timeat every production run, which was considered undesirable.

5-4 WAFSOPSG/2

5.3.3 With regard to the vertical depth of the jetstream, it was further suggested by the userorganizations that consideration should be given to replacing the height convention, currently expressed interms of differences in flight levels (i.e. +/-) by a height convention using flight levels; the current conventionwas considered confusing and not understood by users and States. The group agreed that such a changewould be warranted and should form part of Amendment 74 to Annex 3.


Conclusion 2/8 — Depiction of the vertical depth of the jetstream

That, concerning Appendix 1 to Annex 3, WMO be invited to consider:

a) deleting Examples 1 and 2 under “Model SWH”; and

b) amending Example 3 under “Model SWH” to

1) include only one jet depth information group per jetstreammaximum; and

2) change the depiction of the jet depth, currently expressed interms of differences in flight levels, to that using flight levels.

Note.— These changes should be part of draft Amendment 74 to Annex 3.

5.3.5 Concerning the Guidelines for representing WAFS SIGWX data in BUFR, kept up-to-dateby WAFC London and included in the WAFSOPSG website, it was proposed that, in response toConclusion 15/34 of the APANPIRG calling for the automatic depiction of SIGWX forecasts in chart formfrom BUFR-coded WAFS products, a provision be included therein requiring the software to automaticallyproduce compliant SIGWX charts from the BUFR code for the standard ICAO areas of coverage. In thisregard, WAFC London had assessed the viability of this requirement by consulting with the workstationvendors who had expressed support for this proposal. The group shared the views by WAFC London andworkstation vendors, and considered that the requirement was both practical and beneficial to users.

5.3.6 With regard to the term “automated production”, the group concurred with the interpretationproposed by WAFC London whereby a software application should automatically produce compliant SWHfor the standard ICAO areas and SWM charts for the four areas (Europe, Asia South, Middle East and NorthAtlantic) following either a human induced request or a query placed via a Macro or similar command orapplication. The charts themselves would be produced without the need for any further quality control orhuman intervention.



Conclusion 2/9 — Automatic production of WAFS SIGWX charts fromthe BUFR code

That, the WAFC London be invited to

a) amend the Guidelines for representing WAFS SIGWX data inBUFR requiring that the WAFS visualisation software be capableof automatically generating compliant SIGWX charts from theBUFR code for the standard ICAO areas; and

b) bring the amended guidelines to the attention of software vendors.

Note.— This requirement concerns the automatic production of compliantSWH charts for all the standard ICAO areas and SWM charts for the four areas(i.e. Europe, Southern Asia, Middle East and North Atlantic) as specified in theICAO ANP/FASID, following either a human induced request or a query placedvia a Macro or similar command or application.

5.3.8 With regard to the plotting of coinciding tropical cyclone, volcano and/or radiation events,the group endorsed a new plotting scheme, for inclusion in Annex 3, which would give the highest priorityto volcanic ash, followed by radiation events and tropical cyclones. The order of priority was based on aninformal consultation with IATA.

5.3.9 It was agreed that, in the event of co-incident or the partial overlapping of two or three ofthese phenomena, the phenomena of highest priority would be plotted at the location of the event, and thatan arrow would be used to link the location of the other feature (or features) to its associated symbol or textbox. Such a prioritisation scheme would ensure the legibility of WAFS SIGWX charts at all times.

5.3.10 It was noted that the proposal would need to be adopted by all end users of the WAFSSIGWX BUFR code to ensure that consistent SIGWX charts were produced. The proposal would need to beincorporated into the latest BUFR visualisation software produced by the software vendors and subsequentlyto be made available to users. Even though this was a relatively trivial technical change, it would requirecoordination to ensure that all users take advantage of the format.

5.3.11 The group reviewed the proposal and agreed that the methodology should be adopted andincluded in Amendment 74 to ICAO Annex 3. In this regard, the group formulated the following conclusion:

RSPP Conclusion 2/10 — Amendment to Annex 3 concerning the prioritisationof plotting volcanoes, tropical cyclones and radiationsymbols on WAFS SIGWX charts

That the proposal to amend Annex 3 — Meteorological Service for InternationalAir Navigation given in Appendix E to this report be included as part ofAmendment 74 to Annex 3.

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5.3.12 It was noted that, with regard to information on volcanic ash, that the amendment proposalincluded in Appendix C had eliminated the requirement to include a volcano number in the SIGWX charts.The volcano number had been suppressed in response to Conclusion 1/26 of the IAVWOPSG/1 Meeting.

5.4 Development of WAFS output performance indicators

5.4.1 The group recalled that the IATA Member of the WAFSOPSG, in close coordination withthe IFALPA Member of the WAFSOPSG and the WAFC Provider States, had been tasked to developproposals for WAFS output performance indicators for consideration by the WAFSOPSG. The group notedthat the proposal developed by IATA was based on the root-mean square (RSM) errors of 24-hour windvector and temperature forecasts at FL 340 (250 hPa) over six selected areas, and the availability (expressedin percentage) and timeliness of BUFR- and GRIB-coded WAFS forecasts. The choice of the indicators wasbased on the fact that these were considered to be the most important forecasts for aircraft operations;moreover, WAFCs were in a position to produce these indicators with little effort as they were readilyavailable at the WAFCs and would therefore provide an excellent track record.

5.4.2 The group considered that the above performance measurements were sufficient for thepurpose of trial implementation to indicate the efficiency of the WAFCs with regard to accuracy andtimeliness and agreed that this information should be provided by the WAFC Provider States, on a quarterlybasis using monthly statistics, to the Secretariat for inclusion in the WAFSOPSG website. The groupformulated the following conclusion:

Conclusion 2/11 — WAFS output performance indicators

That the WAFC London Provider States, in coordination with WAFCWashington, be invited to

a) implement, on a trial basis, the following performance indicators:

1) RMS vector wind error for 250hPa (FL340) at T+24 for

— North Atlantic (40N075W-70N090W-70N015E-40N000E)— North Pacific (30N120E-75N120E-75N120W-30N120W)— Asia (25N060E-65N060E-65N145E-25N145E)— Northern Hemisphere (30N-90N)— Tropics (30N-30S)— Southern Hemisphere (30S-90S)

2) RMS temperature error for 250hPa (FL340) at T+24 for

— North Atlantic (40N075W-70N090W-70N015E-40N000E)— North Pacific (30N120E-75N120E-75N120W-30N120W)— Asia (25N060E-65N060E-65N145E-25N145E)— Northern Hemisphere (30N-90N)— Tropics (30N-30S)— Southern Hemisphere (30S-90S)


3) availability (in percentage) of BUFR and GRIB data at theWAFCs;

b) provide the information to ICAO, on a quarterly basis usingmonthly statistics, for inclusion in the WAFSOPSG website; and

c) prepare a report, in coordination with the IATA Member of theWAFSOPSG, on these trials, for consideration by theWAFSOPSG/3 Meeting, in view of the future operationalimplementation of the WAFS output performance indicators by theWAFC Provider States.

5.5 Availability of WAFS forecasts in chart form beyond 1 July2005

5.5.1 The group was aware of the fact that at the MET Divisional Meeting (2002), it had beenagreed that the WAFS forecasts in T4 chart form should be phased out by 1 July 2005 and that the WAFSupper-air and SIGWX forecasts should be provided exclusively in the GRIB and BUFR code forms,respectively. Although this proposal constituted a major change (i.e. States and users would have to purchasedecoding software which would produce WAFS charts from the GRIB and BUFR bulletins), no adversecomments about the transition towards the GRIB and BUFR code forms had been made at the METDivisional Meeting (2002), nor during the subsequent consultation phase which involved all the ICAOContracting States and international organizations. Furthermore, it was pointed out that States and users hadbeen provided over the last few years with a wealth of information concerning the use of the GRIB and BUFRcode forms, inter alia, through regional workshops that had taken place in all the ICAO Regions.

5.5.2 Under these circumstances, it would appear that the States and users should be well preparedfor the change on 1 July 2005, i.e. for the exclusive use of the GRIB and BUFR code forms. However, thegroup noted with concern that problems had been singled out by States and users concerning the use of theBUFR code form as of 1 July 2005. These issues had been raised by the APANPIRG Conclusion 15/32 andEANPG Conclusion 46/24, calling for the WAFSOPSG to consider whether the WAFC Provider States couldcontinue to issue WAFS SIGWX forecasts in chart form, for a limited period of time. The formulation ofthese conclusions had been prompted by the delays in the development of BUFR-coded WAFS forecasts bythe WAFC Provider States (e.g. SWM forecasts in the BUFR code form expected to be available only in April2005) and slower-than-expected availability from software vendors of decoding software that could be usedfor producing WAFS charts compatible with the Guidelines for representing WAFS SIGWX data in BUFRdeveloped by the WAFC London Provider State. It was emphasized that these conclusions did not concernthe GRIB code form, nor did they question the desirability of reaching the final goal identified by the METDivisional Meeting (2002), i.e. the exclusive use of the BUFR code form for the SIGWX forecasts within theWAFS. They would simply facilitate the smooth transition to the new environment, by allowing States andusers to purchase the necessary software during a longer transition period.

5.5.3 The group concurred with the APNPIRG and EANPG, i.e. the issuance of SIGWX forecastsin chart form should be continued, in parallel with the use of BUFR code form, for a limited period of timebeyond 1 July 2005. The group also agreed that ICAO Regional Offices should carry out a survey in May2006 to verify the implementation of the reception and utilization of BUFR-coded SIGWX forecasts byStates, and that the Secretariat should present the results of this consultation for consideration and future

5-8 WAFSOPSG/2

action by the WAFSOPSG/3 Meeting. Since the WAFSOPSG/3 Meeting was expected to take place inSeptember 2006, it was considered reasonable that the provision of SIGWX forecasts in chart form shouldcontinue until 30 November 2006, i.e. an additional period of 17 months; if an additional extension wereconsidered necessary, the WAFSOPSG/3 Meeting would still be in a position to consider prolonging theprovision of SIGWX forecasts in chart form beyond 30 November 2006. This course of action would meetthe intent of the APANPIRG and EANPG conclusions, and it was reasonable to expect that States and userswould be able to purchase the necessary BUFR decoding software in time for the new cut-off date.

5.5.4 In this regard, the group formulated the following conclusion:

Conclusion 2/12 — Extension of the provision of SIGWX forecasts in chartform beyond 1 July 2005 for a limited period of time byWAFC London and Washington

That in view of the initial implementation problems and delays concerning theBUFR-coded SIGWX forecasts,

a) the WAFC Provider States extend the provision of SIGWX forecasts in T.4 chartform beyond 1 July 2005, for a limited period of time until 30 November 2006;

Note 1.— The provision of upper-wind and upper-air temperature forecasts inchart form will cease on 1 July 2005.

Note 2.— This will be accomplished via satellite broadcasts, if practicable oralternatively via the Internet.

b) ICAO Regional offices carry out a survey in May 2006 to verify theimplementation of the reception and effective utilisation of BUFR-codedSIGWX forecasts by States; and

c) the Secretariat present the results of this consultation for consideration andfuture action by the WAFSOPSG/3 Meeting.

5.5.5 An additional proposal related to SIGWX forecasts in chart form was made by the WAFCLondon Provider State which suggested that the provision of WAFS SIGWX charts for the fixed ICAO areasof coverage in chart form using the industry standard Portable Network Graphics (PNG) graphical format (oran equivalent industry standard) be introduced and that these charts be placed on the WAFS FTP server by1 July 2005. The group agreed to this proposal with the understanding that these charts would be providedon a trial basis, with a marginal cost and that the provision of these charts would not question the migrationto the use of the BUFR-coded SIGWX forecasts, as stipulated by Annex 3. The desirability to provide thesecharts on a permanent basis by the WAFCs in the future would be evaluated by the WAFSOPSG/3 Meeting.



Conclusion 2/13 — Availability of WAFS SIGWX forecasts in chart formusing the PNG format or an equivalent industrystandard

That, the WAFC Provider States be invited to

a) provide, on a trial basis, WAFS SIGWX forecasts in chart form for the fixedICAO areas of coverage using the industry standard Portable Network Graphics(PNG) graphical format or an equivalent industry standard;

b) place these charts on the WAFS FTP server by 1 July 2005; and

c) report back to the WAFSOPSG/3 Meeting to facilitate the group to assess thedesirability of continuing the provision of WAFS SIGWX forecasts in chartform using the PNG format or an equivalent industry standard.

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6.1 Requirements for additional maximum wind levels

6.1.1 The group recalled that, at its first meeting, it had formulated Conclusion 1/13 calling for theWAFSOPSG member from IATA to assess user requirements for additional wind levels and report back tothe WAFSOPSG/2 Meeting. Based on a consultation amongst airlines concerning the need for additionalwind levels, it was recognized by IATA that whilst the overall benefits for airlines would be fairly marginal,the sum of the minimal benefit over all flights per year could be expected to provide a quick return on theinvestment made if additional wind levels were implemented. In particular, long-haul flights could takeadvantage of the higher accuracy, due the greater variety of possible routes and vertical levels. Therefore,users supported, in principal, the inclusion of two additional levels between FL 300 and 400 (e.g. FL 320and 370).

6.1.2 It was noted that a related proposal had been made by the 40th Meeting of the NAT SPGwhich had called for the WAFSOPSG to consider the possibilities to refine the temporal resolution of upperwind forecasts, in order to improve the accuracy of ATS estimates. It was expected by the NAT SPG thatthe findings by the WAFSOPSG would be reported back to the NAT SPG/41, to be convened in June 2005(Conclusion 40/4 refers). The NAT SPG had felt that the use of more up-to-date wind data could contributein reducing the risk associated with the reductions in separation minima. Therefore, the NAT SPG consideredthat the temporal resolution of WAFS wind forecasts should be made as fine as economically feasible.

6.1.3 The group agreed that the issue raised by the NAT SPG merited consideration. However,it was understood that it would not be feasible to draw any conclusions by June 2005, i.e. in time for theNAT SPG/41 Meeting since studies to be undertaken by the WAFC Provider States would require more time.

6.1.4 To encompass both the issue of temporal and vertical resolutions, the group agreed that theWAFC Provider States should be invited to assess the impact of improving the spatial and temporalresolutions of upper wind forecasts (e.g. adding two levels between FL 300 and 400, and changing thehorizontal resolution to 60 km and the temporal resolution from 6 to 3 hours or less). It was considered that,as part of this study, the WAFCs should also consider whether improved resolutions should be applied toother forecasts (e.g. temperature) in the GRIB code form. It was expected that the results of these studieswould be made available to the WAFSOPSG/3 Meeting.

6-2 WAFSOPSG/2


Conclusion 2/14 — Improvements in the temporal and spatialresolution of WAFS upper wind forecasts


a) study the possibility of improving the temporal and spatialresolution of WAFS upper wind and other upper-air forecasts in theGRIB code form, including their financial implications; and

b) report back to the WAFSOPSG/3 Meeting.

Note 1.— The impact of the following improvements is expected to beaddressed:

C vertical resolution: addition of two levels between FL 300 and 400 (e.g.FL 320 and 370); C horizontal resolution: improvement to 60 km; andC temporal resolution: increase to 3 hours or less.

Note 2.— The work programme of the WAFSOPSG would have to beamended accordingly under Agenda Item 7.

6.2 Development of quantitative airframe icing intensity criteria

6.2.1 The group was aware of the fact that it had requested (Conclusion 1/15 refers) the WAFCProvider States to present a progress report on the development of an objective icing index to be used inWAFS SIGWX forecasts, for consideration by the WAFSOPSG/2 Meeting. The WAFC WashingtonProvider State presented results from on-going work related to the reporting of icing in the United States.However, no proposals for an icing index were included therein; the development of such an index wasconsidered to be closely related to the progress that was being made in the development of improved WAFSoutput product for icing. As this development work had not been completed yet, no proposals on the icingindex were made by the WAFC Provider States.

6.2.2 The group reiterated its point of view expressed at the WAFSOPSG/1 Meeting whichunderscored the importance of such an index; it would harmonize icing information to be included in thefuture output product for icing by the two WAFCs. It could also be used by MWOs to issue SIGMET inthose States that use numerical weather prediction models. Under these circumstances, the group encouragedthe WAFC Provider States to pursue work on this important issue and formulated the following conclusion:

Conclusion 2/15 — Development of an objective icing index

That, the WAFC Provider States be invited to present a progress report on thedevelopment of an objective icing index to be used in new WAFS output productfor icing, for consideration by the WAFSOPSG/3 Meeting.


6.3 Development of improved WAFS output products for icingand turbulence

6.3.1 The group recalled that it had formulated Conclusion 1/16 calling for the WAFC ProviderStates to pursue work on the development of new WAFS output products for turbulence and icing in gridpoint format and to report back to the WAFSOPSG/2 Meeting. The group reviewed the detailed progressreport provided by WAFC London Provider State related to the development of automated forecasts of icing,turbulence and CB/TCU, and was encouraged by the progress made. The group was pleased to note that thedevelopment work undertaken also included forecasts for convective clouds (i.e. CB/TCU clouds) which lentthemselves to presentation in the GRIB code form. The group endorsed the product description (AppendixF refers) and agreed that WAFC Provider States should carry out verification of the trial forecasts and reportthe results thereof back to the WAFSOPSG/3 Meeting (2006). It was further agreed that the developmentwork should be progressed in view of its completion by the WAFSOPSG/4 Meeting (2008). The grouprealized that this “road map” was expected to lead to the operational implementation of the new outputproducts for icing, turbulence and convective clouds as part of Amendment 75 to Annex 3 (November 2010).

6.3.2 In order to accelerate progress in the development of WAFS output products for turbulence,icing and convective clouds (CB and TCU), the group formulated the following conclusion:

Conclusion 2/16 — Development of improved forecasts for icing,turbulence and CB/TCU in the grid point format

That, taking due account of the results from the “Icing and turbulenceworkshop”, held at Exeter in February 2005, the WAFC Provider States beinvited to

a) continue work on the development of improved WAFS outputproducts for icing, turbulence and CB/TCU, based on the productdescription given in Appendix F to this report;

b) carry out verifications of the trial forecasts and report back theresults thereof to the WAFSOPSG/3 Meeting (2006); and

c) progress development work in view of its completion, including theoperational trials, by the WAFSOPSG/4 Meeting (2008).

Note.— The establishment of appropriate GRIB2 tables, in coordinationwith WMO, will form part of this development work.

6-4 WAFSOPSG/2

6.4 Feasibility of amending the lead time for issuance of SIGWXforecasts

6.4.1 With regard to the lead time for issuance of SIGWX forecasts, the group recalled that it hadformulated Conclusion 1/18 calling for the WAFC Provider States to develop verification methodology forelements included in SIGWX forecasts, with verification of 24-, 30- and 36-hr forecasts to be made againstmodel analysis. The WAFC Provider States had also been requested to study the possibility of issuing twoparallel SIGWX forecasts.

6.4.2 The results of these studies suggested that neither the issuance of T+30 hr or T+36 hr SIGWXforecasts, nor that of parallel SIGWX forecasts would be recommendable; the provision of T+30 hr orT+36 hr SIGWX forecasts would lead to the significant degradation of forecast accuracy compared to T+24hr while the introduction of parallel SIGWX forecasts would involve duplicating the production process,which would be excessive as far as costs were concerned. The group concurred that these options were notviable and that there was no need to pursue work on the issuance of SIGWX forecasts valid beyond 24 hours;the development of gridded forecasts of icing, turbulence and convective clouds (CB and TCU) up to T+36hr discussed under 6.3 above held the promise of providing airlines and other users with the information theyrequired to plan for longer-haul flights by the year 2010. To address the shorter-term needs of airlines, it wasagreed that the WAFCs should advance the lead time of issuance of the existing SIGWX products as soonas practicable; they group was pleased to note that both the high-level and medium-level SIGWX forecastswere available, at the latest, 13.5 hr before their validity time. The group considered that this solution wouldprovide the advantages that the users were looking for without any detriment to accuracy. Furthermore, theWAFC Provider States were invited to consider the possibility of advancing the lead time further to 17 hours.

6.4.3 In this regard, the group formulated the following conclusions:

RSPP Conclusion 2/17 — Amendment to Annex 3 concerning the lead time ofissuance of SIGWX forecasts

That the proposal to amend Annex 3 — Meteorological Service for InternationalAir Navigation given in Appendix G to this report be included as part ofAmendment 74 to Annex 3.

Conclusion 2/18 — Advancing the lead time of issuance of SIGWXforecasts


a) investigate the feasibility of issuing the SIGWX forecasts up to 17hours before their validity time; and

b) report the results to the WAFSOPSG/3 Meeting.


6.5 Future requirements for WAFS SWM forecasts

6.5.1 When addressing the future requirements for WAFS SWM forecasts, the group had agreedthat the WAFC Provider States should be invited to study the feasibility of replacing the WAFS SWMforecasts by new global WAFS output products for turbulence, icing and convective clouds (CB and TCU)in grid point format and if feasible, the Secretariat should develop the corresponding amendment to Annex3 (Conclusion 1/26 refers). This had been considered as an optimal solution which would also meet therequirements by airline users.

6.5.2 As indicated in Section 6.3 above, the development of the new WAFS output products waswell underway. However, work had not been completed in this area and therefore, it would not be possibleto replace the WAFS SWM forecasts by new global WAFS output products for turbulence, icing andconvective clouds (CB and TCU) in grid point format at this stage. It was expected that the replacementcould take place as part of Amendment 75 to Annex 3, subject to the implementation of the GRIB2 code form(Section 6.6 refers). Under these circumstances, it was agreed that WAFS SWM forecasts should, for thetime being, continue to be issued. The group formulated the following decision:

Decision 2/19 — Future of the SWM forecasts

That, the SWM forecasts for limited geographical areas, in accordance withregional air navigation (RAN) agreement, continue to be provided by the WAFCProvider States until their replacement by new global output products forturbulence, icing and convective clouds (CB and TCU).

6.6 Migration to the GRIB2 code form

6.6.1 The group was aware that migration from the current GRIB1 code form to the future GRIB2code form was taking place within WMO. Since there was no room for expansion in the GRIB1 code form,the group had realized at its first meeting that the WAFCs would not be in a position to use the GRIB1 codeform for new output products, and that a migration to the GRIB2 code form would be necessary. In orderto assess the effects of this migration, the group had called for the WAFC Provider States to sudy the impactof migration to the GRIB2 code form within the WAFS, addressing both the costs and benefits for WAFCsand WAFS users, and to report the results of these studies to the WAFSOPSG/2 Meeting.

6.6.2 It was noted that the progress in this area had been slow, partly due to the slower-than-expected transition within the WMO community and that so far, few States had taken steps for migrating fromthe GRIB1 to GRIB2 code form. Therefore, no results could be reported by the WAFC Provider States.

6.6.3 Irrespective of the current status of the transition, it appeared clear to the group that, in orderto be able to introduce the new WAFS output products for icing, turbulence and convective clouds (CB andTCU), it was necessary to migrate to the GRIB2 code form within WAFS. This should be completed in timefor Amendment 75 to Annex 3. The group agreed that, to ensure an orderly and timely migration to theGRIB2 code form within WAFS, the WAFC Provider States, in coordination with the WAFSOPSG Memberfrom WMO, should develop a migration plan. The group formulated the following conclusion:

6-6 WAFSOPSG/2

Conclusion 2/20 — Migration to the GRIB2 code form

That, the WAFC Provider States, in coordination with the WAFSOPSG Memberfrom WMO, be invited to

a) prepare a migration plan to the GRIB2 code form within WAFS intime for Amendment 75 to Annex 3 (2010), addressing in particular,the costs and benefits for WAFCs and WAFS users; and

b) present the plan to the WAFSOPSG/3 Meeting for endorsement.

6.7 Quality control of MET information in the ADS messages

6.7.1 With regard to the quality control of MET information in the ADS messages, a feasibilitystudy had been undertaken by WAFC London. The results thereof indicated that approximately 1 700reports were received daily by WAFC London. A daily check on the previous days’ data would take about30 minutes. The time required for rectifying a problem could be anything from one to two hours to a fewdays and was also dependant on the fault reporting procedures in place. Experience gained from the WMOAMDAR programme suggested that airlines were very cooperative, and generally faults could be rectifiedin a timely manner. However, the difficulty in providing feed-back in the current, non-ATN compatibleenvironment was highlighted. The group realized that ADS messages had to be coded using the AIREPformat included in Appendix 1 to the PANS-ATM (Doc 4444) and that the AIREP format suffered from twoshortcomings:

a) absence of indication of the type of the report (consequence: distinction betweenADS messages and standard air-reports impossible); and

b) absence of registration number of the aircraft (consequence: provision of feed-backto the operator concerned complicated).

The group was pleased to note that, to address these issues, a draft amendment to Appendix 1 to the PANS-ATM (Doc 4444) had been developed by the ICAO Secretariat, with the assistance of the METLINKSG.

6.7.2 The group understood that the total cost of providing feed-back depended on:

a) the total number of reports received;

b) the proportion of faulty reports;

c) the average time to resolve each fault; and

d) the effectiveness of the fault rectification procedure.

If reports from ten aircraft per month were faulty and it took one hour to resolve each fault, the total costwould be about UKP 10 000 per year.


6.7.3 In light of the results, the group considered that the provision of feed-back to the operatorsconcerned related to the quality of MET information included in the ADS messages was both feasible anddesirable. Therefore, the group tasked the WAFC London Provider State, in close coordination with theWAFC Washington Provider State and the WAFSOPSG Member from WMO, to develop appropriatesoftware for quality control of the meteorological information data block of the ADS messages and contactprocedures for feed-back with operators, based on guidance from ICAO. It was realized that the resultingsoftware could only become operational after the implementation of the new format of AIREP which wouldclearly identify ADS messages and which would include the registration number of the aircraft. The groupformulated the following conclusion:

Conclusion 2/21 — Quality control of the MET information data blockof the ADS messages

That, pursuant to the implementation of the new AIREP format including theregistration number of the aircraft, WAFC Provider States be invited, incoordination with the WAFSOPSG Member from WMO, to develop appropriatesoftware and procedures for quality control of the meteorological informationdata block of the ADS messages.

Note.— This work should include contact procedures for feed-back withoperators.

6.8 Depiction of aerodromes on SIGWX charts

6.8.1 As a result of feedback from airlines operating in Hong Kong, China regarding new SIGWXcharts generated from BUFR-coded WAFS data, it was suggested that aerodromes on the SIGWX chartsshould be indicated using the standard ICAO location indicator, instead of the first letter of the city, ascurrently stipulated by Annex 3. The feedback has also indicated that labels and text boxes should not beplaced over the aerodromes of departure and intended landing, nor over alternate aerodromes.

6.8.2 The group, including users, did not share the view that the identification of aerodromesshould be changed to correspond to ICAO location indicators. It was considered that the proposed additionof three letters could, under certain circumstances, increase clutter and would therefore be undesirable. Thegroup did endorse the proposal to give preference to the letters of the cities over labels and text boxes withthe understanding that the meteorological phenomena would continue to maintain the highest priority at alltimes as far as the display was concerned.


Conclusion 2/22 — Amendment to the Guidelines for presenting WAFSSIGWX data in BUFR concerning the depiction ofaerodrome on SIGWX charts

That, the WAFC London Provider State be invited to amend the Guidelines forpresenting WAFS SIGWX data in BUFR to indicate that labels and text boxesshould not cover the aerodromes of departure and intended landing, nor alternateaerodromes.

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Agenda Item 7: Future work programme

7.1 With regard to the future work programme, the group noted that the Secretary had made anumber of changes to take account of the progress made by the group.

7.2 The group reviewed the work programme, proposed some additional changes based on thediscussions under Agenda Items 5 and 6, and formulated the following conclusion:

Conclusion 2/23 — Update of the work programme of theWAFSOPSG

That, the work programme of the WAFSOPSG be replaced with that shown inAppendix H to this report.

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8.1 SADIS seminar

8.1.1 The group considered a proposal by the WAFC London Provider State to organize aninternational SADIS seminar to bring SADIS stakeholders (users, software suppliers, SADIS 2G hardwaresuppliers, and service providers) together. This seminar would to provide SADIS users with a forum to:

— undertake “networking” between SADIS 2G hardware suppliers and softwaremanufacturers;

— discuss the current and future hardware/ software requirements with thevendors;

— inform about recent and forthcoming changes to the SADIS service; and

— provide the SADIS Provider State with feedback about all aspects of thedelivery of the SADIS service.

As this event would also be of interest to ISCS users, it was considered appropriate that the issue wasaddressed at the WAFSOPSG Meeting.

8.1.2 It was agreed that the event should be organized in coordination with ICAO and WMO. TheICAO European and North Atlantic Office, Paris was considered to be a suitable venue for most SADIS userStates. It was considered that the seminar should last one and a half days. To maximise participation and tominimise travel costs, it was agreed that the event should take place immediately after the 16th Meeting of theMETG of the EANPG, due to convene September 2006, and on Monday and Tuesday (half a day) of the sameweek as the WAFSOPSG/3 Meeting (Tuesday to Friday) (paragraph 8.2.1 refers).


Conclusion 2/23 — International SADIS seminar

That

a) the SADIS Provider State be invited, in coordination with ICAO andWMO, to organise an international SADIS seminar in September 2006 atthe ICAO European and North Atlantic Regional Office; and

b) the Secretariat inform the SADISOPSG accordingly.

Note.— To facilitate the participation of those concerned, theseminar is expected to be organized during the week following the 16th Meetingof the EANPG METG and during the same week as the WAFSOPSG/3 Meeting.

8-2 Report on Agenda Item 8

8.2 WAFSOPSG/3 Meeting

8.2.1 With regard to the WAFSOPSG/3 Meeting, the group recalled that it was the intention toconvene WAFSOPSG Meetings about every 18 months and that the meetings would be held at ICAO regionaloffices on a rotational basis. The group agreed that for planning purposes, the WAFSOPSG/3 Meeting shouldbe convened at the ICAO EUR/NAT Office in September 2006, during the week following the METG/16Meeting and immediately after the proposed SADIS Seminar.

8.3 Liability of WAFC Provider States

8.3.1 The liability of the WAFC Provider States for omissions or errors in WAFS forecasts wasraised. It was considered important to establish whether the liability lay within the WAFC Provider State(s)or within the user State(s) concerned. In this regard, the group was advised by WAFC London Provider Statethat the European Union legislation clearly indicated that the responsibility was within the user Stateconcerned which should consider taking an appropriate insurance to cover itself in the case of a problemoccurring with a forecast issued by the WAFCs. The group also noted that the final responsibility was withthe pilot-in-command who would have to make appropriate operational decisions based on all meteorologicalinformation available.

8.4 Joining two WAFS charts of different fixed time

8.4.1 It was suggested that the current practice of providing fixed valid time WAFS forecasts ofsignificant weather and upper winds did not properly cover the requirements for the entire flight, particularlyfor long-haul flights. It was therefore, proposed that by joining two subsequent fixed valid time WAFS chartsof the same product and level, the information would be more relevant for the whole duration of the flight.It was suggested that this feature of joining two consecutive WAFS charts should be available from thesoftware used to decode BUFR- and GRIB-coded WAFS forecasts. No modification would be made to theoriginal products received from WAFCs; there would simply be a need to write the validity times on thecharts that are joined.

8.4.2 The group noted with interest these proposals; however, it noted that the present Annex 3provisions already allowed such a practice with the proviso that no changes were made to the meteorologicalcontent of the WAFS forecast and that the joined forecasts were labelled correctly. It was considered to beanother matter whether to render this capacity as a mandatory feature in the decoding software or whetherthis should be considered as a value-added product and funded by those users which expressed a requirementfor such a product. The group agreed that this proposal could be re-considered by the WAFSOPSG/3Meeting if an appropriate working paper were issued well in advance to allow an appropriate consultationwith users and software vendors to assess the impact of this proposal.

8.5 Acknowledgements

8.5.1 The group expressed its gratitude to the ICAO Regional Director for excellent arrangementsduring this meeting.

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Appendix A to the Report A-1

APPENDIX A

LIST OF PARTICIPANTS

AUSTRALIA Mr. Ted WilliamsMember

National Manager Aviation WeatherServicesBureau of Meteorology700 Collins StreetMelbourne VIC 3001Australia

Tel: +61 (3) 9669 4586Fax +61 (3) 9669 4695E-mail: [email protected]

BRAZIL Mr. Adahil FranciscoGusmãoMember

Chefe da Seção de MeteorologiaCINDACTA ISHIS QI 05 - Area Especial 1271615-600 Brasilia - DFBrazil

Tel.: +55 (61) 364 8383Fax: +55 (61) 365 1134E-mail: [email protected]

Mr. Martim RobertoMatschinskeAdvisor

Aeronautical Meteorology DivisionMinistry of DefenceAeronautic CommandDepartment of Air Space ControlAv. General Justo, 370Rio de Janeiro, 370CEP 20021-340Brazil

Tel: +55 (21) 2101 6285Fax: +55 (21) 2101 6283E-mail: [email protected]

CANADA Mr. Ken MacdonaldMember

DirectorAviation and Defence ServicesMeteorological Service of CanadaE-1 Block, La Salle Academy373 Sussex DriveOttawa, OntarioCanada K1A 0H3

Tel.: +1 (613) 992-3917Fax: +1 (613) 992 4288E-mail: [email protected]

CHINA Mr. Xu JianliangMember

Senior Engineer of MeteorologicalDivisionAir Traffic Management Bureau,CAACNo. 12, East San-Huan Road MiddleChaoyang District, Beijing, China 100022

Tel.: +86 (10) 8778 6823Fax: +86 (10) 8778 6820E-mail: [email protected] or [email protected]

Mr. Chi-ming ShunPermanent Advisor

Senior Scientific OfficerHong Kong Observatory134A Nathan RoadKowloonHong Kong, China

Tel.: + 852 2926 8435Fax: + 852 2375 2645E-mail: [email protected]

JAPAN Mr. Yuji YamadaObserver

ForecasterNumerical Prediction DivisionJapan Meteorological AgencyOtemachi 1-3-4, Chiyoda-kuTokyo 100-8122Japan

Tel: +81 (3) 3212-8341Fax: +81 (3) 3211-8407E-mail: [email protected]

A-2 WAFSOPSG/2

OMAN Mr. Ahmed Hamoud Mohamed Al HarthyMember

Directorate General of Civil Aviationand MeteorologySeeb International AirportP.O. Box 1, Code: 111 &P.O. Box 204, Code: 113MuscatSultanate of Oman

Tel: +968 (24) 519 360Fax: +968 (24) 518 360E-mail [email protected]

ROMANIA Mr. Dorinel VisoiuMember

Head of MET DivisionRomanian Air Traffic ServicesAdministration (ROMATSA)10, Ion Ionescu de la Brad StreetP.O. box 18.9071592 BucharestRomania

Tel.: +40 (21) 2083 206Fax: +40 (21) 2038 579Mobile: +40 722 645 648E-mail: [email protected]

UNITEDKINGDOM

Mr. Bernard PerryMember

Head of MET AuthorityDirectorate of Airspace PolicyRoom K6G1, CAA House, 45-59 KingswayLondon WC2B 6TEUnited Kingdom

Tel.: +44 (207) 453-6526Fax: +44 (207) 453-6565E-mail: [email protected]

Mr. Nigel GaitAdvisor

International Aviation ManagerThe MET OfficeFitzroy RoadExeterDevon EX1 3PBUnited Kingdom

Tel: +44 (1392) 886268Fax: +44 (1392) 885681Mobile: +44 (7753) 880507E-mail: [email protected]

Mr. Richard M.OrrellAdvisor

Senior International Aviation AnalystThe MET OfficeFitzroy RoadExeterDevon EX1 3PBUnited Kingdom

Tel: +44 (1392) 884892Fax: +44 (1392) 885681Mobile: +44 (7753) 880143E-mail: [email protected]

UNITEDSTATES

Mr. Rick HeuwinkelMember

Manager, Aviation Weather PolicyDivisionATO OPS PlanningFederal Aviation Administration(FAA)800 Independence Ave. SWWashington DC 20591United States


Mr. Kevin Browne Advisor

Staff SpecialistFAA (US) ATO OPS PlanningFederal Aviation Administration(FAA)Attn: ATO-OPS Planning800 Independence Ave. SWWashington DC 20591United States


Appendix A to the Report A-3

Mr. Michael MercerAdvisor

Aviation Weather Requirements &International ServicesNational Weather ServicesAviation Weather Service BranchStation 13316 W/OS231325 East-West HighwaySilver Spring, MD 20910United States

Tel: +1 (301) 713 1726 Ext. 140Fax: +1 (301) 713 1520E-mail: [email protected]

Mr. Larry BurchAdvisor

Deputy DirectorNOAA/NWS/Aviation WeatherCenterWAFC WashingtonNOAA/NWS7220 NW, 101 Street TerraceKansas City, MO 64153United States

Tel: +1 (816) 584 7203Fax: -E-mail: [email protected]

ASECNA M. Akoa BenoitOkossiMember

Direction Générale ASECNADépartment de la MétéorologieB.P. 3144 DakarSenegal

Tel: +221 869 5714Fax: +221 8695714E-mail: [email protected]

IATA Mr Hans-RudiSonnabendMember

Head of Meteorological ServicesFRA OD/N-MLufthansa Systems AeronauticsGmbH Frankfurt FlughafenD-60546 Frankfurt/MGermany


Mr. UrbanWeisshaarAdvisor

IATA AdvisorLufthansa Systems AeronauticsGmbHFRA OD/1D-60546 Frankfurt/MGermany

Tel.: +49 (0) 69 696 93994Fax: +49 (0) 69 696 91363E-mail: [email protected]

IFALPA Captain Jan RozemaMember

IFALPADomaine Le Grand DucAvenue MonteverdiF06210 MandelieuFrance

Tel: +33 49 349 2705Fax: +33 84 704 84552 E-mail [email protected]

Mr. Brett HuttonAdvisor

Cathay Pacific Airways LimitedFlight Operations DepartmentCrew Mail Box 269Cathay Pacific City8 Scenic RoadHong Kong International AirportLantau IslandHong Kong

Tel.: +852 2987 2499Fax: +852 2987-2499E-mail: [email protected]

A-4 WAFSOPSG/2

WMO Mr. N. Tata DialloMember

Aeronautical Meteorology UnitApplications DepartmentWorld Meteorological Organization7 bis, avenue de la PaixCase postale 2300CH-1211, Geneva 2Switzerland

Tel: +41 (22) 730 8283Fax: +41 (22) 730 80 21E-mail: [email protected]

Mr. Jeff SticklandAdvisor

Technical Co-ordinator, WMOAMDAR PanelBureau of MeteorologyP.O. Box 1289KGPO Mebourne, Victoria 3001Australia

Tel: +61 (3) 9669-4255Fax: +61 (3) 9669-4168E-mail: [email protected]

SECRETARIAT Dr. Olli MariusTurpeinen

Chief, Meteorology SectionAir Navigation BureauInternational Civil AviationOrganization (ICAO)999 University St.Montreal, QuebecCanada H3C 5H7


Mr. Dimitar H.Ivanov

Regional Officer METInternational Civil AviationOrganization (ICAO) 251/1, Vibhavadee Rangsit RoadLadyao, Chathuchak Bangkok 10900

Tel: +66 (2) 537 8189Fax: +66 (2) 537 8199E-mail [email protected]

— — — — — — — —

Appendix B to the Report B-1

APPENDIX B

ANP/FASID PROVISIONS RELATED TO WAFS

BASIC ANP

. . .

World area forecast system (WAFS)(FASID Tables MET 5, MET 6 and MET 7)

1. FASID Table MET 5 sets out the [AFI, ASIA/PAC, CAR/SAM, EUR, MID, NAT] Region[s]requirements for WAFS forecasts to be provided by WAFC [London, Washington].[WAFSOPSG Conclusion 1/2]

2. The levels for which forecasts of SIGWX in chart form are to be provided by the WAFC [London,Washington] and the areas to be covered by these charts are indicated in FASID Table MET 5.[WAFSOPSG Conclusion 2/2]

Note.— WAFCs will continue to issue forecasts of SIGWX in chart form until 30 November 2006.

3. FASID Table MET 6 sets out the responsibilities of WAFCs London and Washington for theproduction of WAFS forecasts. For back-up purposes, each WAFC should have the capability toproduce WAFS forecasts for all the required areas of coverage.[WAFSOPSG Conclusion 1/2]

4. The projection of the WAFS forecasts in chart form and their areas of coverage should be as indicatedin FASID Charts MET 4, MET 5 and MET 6 associated with FASID Table MET 6; their scale shouldbe 1:20 X 106, true at 22.50 in the case of charts in the Mercator projection, and true at 600 latitudein the case of charts in the polar stereo-graphic projection.[WAFSOPSG Conclusion 1/2]

Note.— WAFCs will continue to issue forecasts of SIGWX in chart form until 30 November 2006.

5. WAFS products should be disseminated by WAFC [London, Washington] using the [satellitedistribution system for information relating to air navigation (SADIS), international satellitecommunications system (ISCS1, ISCS2)] covering the reception area shown in FASID Chart CNS [4].[WAFSOPSG Conclusion 2/2]

6. The amendment service to the SIGWX forecasts issued by WAFCs London and Washington shouldbe by means of amended BUFR files disseminated through [SADIS, ISCS1, ISCS2].[WAFSOPSG Conclusion 1/2]

7. Each State should make the necessary arrangements to receive and make full operational use ofWAFS products disseminated by WAFC [London, Washington]. FASID Table MET 7 lists theauthorized users of the [SADIS, ISCS1, ISCS2] satellite broadcast in the [AFI, ASIA/PAC,CAR/SAM, EUR, MID, NAT] Region[s] and location of the operational VSATs.[WAFSOPSG Conclusion 1/2]

B-2 WAFSOPSG/2

FASID

World area forecast system (WAFS)(FASID Tables MET 5, MET 6 and MET 7FASID Charts MET 4, MET 5, MET 6 and MET 7)

1. FASID Table MET 5 sets out the [AFI, ASIA/PAC, CAR/SAM, EUR, MID, NAT] Region[s]requirements for WAFS forecasts, to be provided by WAFC [London, Washington].

2. FASID Table MET 6 sets out the responsibilities of WAFCs London and Washington for theproduction of WAFS forecasts. The fixed areas of coverage of WAFS forecasts in chart form areshown on FASID Charts MET 4, MET 5, MET 6 and MET 7.

Note. — WAFCs will continue to issue forecasts of SIGWX in chart form until 30 November 2006.

3. FASID Table MET 7 lists the authorized users of the [SADIS, ISCS1, ISCS2] satellitebroadcast in the [AFI, ASIA/PAC, CAR/SAM, EUR, MID, NAT] Region[s] and location of the operationalVSATs. The table is included in the FASID for information purposes and kept up-to-date by the RegionalOffices concerned.


FASID TABLE MET 5 — REQUIREMENTS FOR WAFS PRODUCTS

EXPLANATION OF THE TABLE

Column

1. WAFS products required by the [AFI, ASIA/PAC, CAR/SAM, EUR, MID, NAT] States, to beprovided by WAFC [London, Washington].

2. Area of coverage required for the WAFS forecasts, to be provided by WAFC [London, Washington].

FORECAST REQUIRED AREAS REQUIRED

1 2

SWH CHART (FL 250 - 630) [A, B, B1, C, D, E, F, G, H, I, J, K, M]

SWM/SWH CHART (FL 100 - 450) [NIL or ASIA SOUTH, EUR, MID, NAT]

SWH forecasts (FL 250-630) in the BUFR code form GLOBAL

SWM forecasts (FL 100-250) in the BUFR code form [NIL or ASIA SOUTH, EUR, MID, NAT]

Upper-air wind, temperature, altitude of flight levelsand humidity forecasts in the GRIB code form

GLOBAL

Note 1.— Combined SWM/SWH charts are provided for limited geographical areas asdetermined by regional air navigation agreement. The chart covers the SWH range only up to FL 450.

Note 2.— WAFCs will continue to issue forecasts of SIGWX in chart form until 30 November2006.

B-4 WAFSOPSG/2

FASID TABLE MET 6 — RESPONSIBILITIES OF THE WORLD AREA FORECAST CENTRES

EXPLANATION OF THE TABLE

Column

1 Name of the world area forecast centre (WAFC).

2 Area of coverage of significant weather (SIGWX) forecasts in the BUFR code formprepared or relayed by the WAFC in Column 1.

3 Area of coverage of the SIGWX forecasts in chart form prepared or relayed by the WAFCin Column 1.

4 Area of coverage of upper-air wind, temperature, altitude of flight levels and humidityforecasts in the GRIB code form issued by the WAFC in Column 1.

WAFCAreas of coverage of

SIGWX forecasts Upper-air wind, temperature, altitude offlight levels and humidity forecasts

In the BUFR code form In chart form In the GRIB code form

1 2 3 4

London SWH (FL 250 - 630): global

SWM (FL 100 - 250):ASIA SOUTH,EUR and MID

SWH (FL 250 - 630): B, C, D, E, G, H and K

SWM/SWH (FL100-450): ASIA SOUTH, EURand MID

global

Washington SWH (FL 250 - 630):global

SWM (FL 100- 250):NAT

SWH: (FL 250 - 630)A, B1, F, H, J, I and M

SWM/SWH (FL100 - 450): NAT

global

Note. — WAFCs continue to issue forecasts of SIGWX in chart form until 30 November 2006.


FIXED AREAS OF COVERAGE OF WAFS FORECASTS IN CHART FORM – MERCATOR PROJECTION

FASID Chart MET 4

FIXED AREAS OF COVERAGE OF WAFS FORECASTS IN CHART FORM – POLAR STEREOGRAPHICPROJECTION (NORTHERN HEMISPHERE)

FASID Chart MET 5

FIXED AREAS OF COVERAGE OF WAFS FORECASTS IN CHART FORM – POLAR STEREOGRAPHICPROJECTION (SOUTHERN HEMISPHERE)

FASID Chart MET 6

B-6 WAFSOPSG/2

FASID TABLE MET 7 — AUTHORIZED USERS OF THE [SADIS, ISCS1, ISCS2] SATELLITE BROADCAST AND THE

INTERNET-BASED WAFS FTP SERVICE IN THE [AFI, ASIA/PAC, CAR/SAM, EUR, MID,NAT] REGION[S]

EXPLANATION OF THE TABLEColumn

1 Name of the State or territory.

2 User of the satellite broadcast. Abbreviations used:

CAA — civil aviation authorityNMS — national meteorological serviceO — other than the civil aviation authority or the national meteorological service.

3 Location of VSAT: town and, where applicable, aerodrome to be indicated.

4 Indication whether the equipment is operational:

2w — two-way VSAT operational 1w — one-way VSAT operational F — only WAFS Internet-based FTP service[blank] — no.

[Satellite Distribution System for Information Relating to Air Navigation (SADIS) , International Satellite CommunicationSystem (ISCS1, ISCS2)] provided by the [United Kingdom, United States]

State/Territory User of satellitebroadcast Location of VSAT Equipment

operational

1 2 3 4

Editorial Note. — The content of the FASID Table MET 7 is to be kept up-to-date by the PIRGs andregional offices concerned.

— — — — — — — —

Appendix C to the Report C-1

APPENDIX C

PROPOSED AMENDMENT TO

INTERNATIONAL STANDARDS AND RECOMMENDED PRACTICES

METEOROLOGICAL SERVICE FOR INTERNATIONAL AIR NAVIGATION

ANNEX 3TO THE CONVENTION OF INTERNATIONAL CIVIL AVIATION

FIFTEENTH EDITION — JULY 2004

PART I — Core SARPs

CHAPTER 1. DEFINITIONS

Editorial Note.— Delete the definition for “service area (world area forecast system)”

CHAPTER 3. WORLD AREA FORECAST SYSTEMAND METEOROLOGICAL OFFICES

Note. — Technical specifications and detailed criteria related to this chapter are given in Appendix 2.

WAFSOPSG 1/28

3.1 Objective of theworld area forecast system

The objective of the world area forecast system shall be to supply meteorological authorities and other userswith global aeronautical meteorological en-route forecasts of global upper wind, upper-air temperature andhumidity, direction, speed and height of maximum wind, tropopause height and temperature and forecasts ofsignificant weather phenomena in digital form. This objective shall be achieved through a comprehensive,integrated, worldwide and, as far as practicable, uniform system, and in a cost-effective manner, taking fulladvantage of evolving technologies.

C-2 WAFSOPSG/2

3.2 World area forecast centres

3.2.1 A Contracting State, having accepted the responsibility for providing a WAFC withinthe framework of the world area forecast system, shall arrange for that centre:

a) to prepare global forecasts for grid points in digital form for all required levels and in a standardformat; the forecasts shall comprise global forecasts of

1) upper winds,;

2) upper-air temperatures and humidity,;

3) altitude of flight levels;

4) tropopause heights altitude and temperatures; and

5) direction, speed and altitude of maximum wind speed, direction and height;

b) to prepare global forecasts of significant weather (SIGWX) phenomena in digital form;

c) to issue the forecasts referred to in a) and b) in digital form to meteorological authorities and otherusers in its service area, as approved by the Contracting State on advice from the meteorologicalauthority;

WAFSOPSG 1/25

d) to prepare and issue amendments to the forecasts;

ed) to receive information concerning the accidental release of radioactive materials into theatmosphere from its associated WMO regional specialized meteorological centre for the provisionof transport model products for radiological environmental emergency response, in order to includethe information in significant weather SIGWX forecasts; and

fe) to establish and maintain contact with VAACs for the exchange of information on volcanic activityin order to coordinate the inclusion of information on volcanic eruptions in significant weatherSIGWX forecasts.

WAFSOPSG 1/1

Note 1.— Specifications for the preparation of significant weather and upper-air prognostic charts arecontained in Part II, Appendix 1.


Note 2.— The WAFS service areas are given in the regional air navigation plans.

3.2.2 In case of interruption of the operation of a WAFC, its functions shall be carried out by theother WAFC.

Note. — Back-up procedures to be used in case of interruption of the operation of a WAFC are givenin Attachment C. Back-up procedures are expected to be subject to minor revisions by the World Area ForecastSystem Operations Group (WAFSOPSG) and the latest revision can be found at the WAFSOPSG website at:www.icao.int/anb/wafsopsg.

. . .

CHAPTER 6. FORECASTS

. . .

Editorial Note.— Delete Section 6.5 in toto.

6.65 Area forecasts for low-level flights

Editorial Note.— Renumber 6.6.1 to read 6.5.1.

. . .

6.65.2 When the density of traffic operating below flight level 100 warrants the issuance of AIRMETinformation in accordance with 7.2.1, area forecasts for such operations shall be prepared in a format agreedupon between the meteorological authorities concerned. When abbreviated plain language is used, the forecastshall be prepared as a GAMET area forecast, employing approved ICAO abbreviations and numerical values;when chart form is used, the forecast shall be prepared as a combination of forecasts of upper wind and upper-air temperature, and of SIGWX phenomena. The area forecasts shall be issued to cover the layer between theground and flight level 100 (or up to flight level 150 in mountainous areas, or higher, where necessary) andshall contain information on en-route weather phenomena hazardous to low-level flights, in support of theissuance of AIRMET information, and additional information required by low-level flights.

Editorial Note.— Renumber 6.6.3 to read 6.5.3.

. . .

C-4 WAFSOPSG/2

CHAPTER 9. SERVICE FOR OPERATORSAND FLIGHT CREW MEMBERS

Note.— Technical specifications and detailed criteria related to this chapter are given in Appendix 8.

9.1 General provisions

9.1.1 Meteorological information shall be supplied to operators and flight crew members for:

a) pre flight planning by operators;

b) in-flight re planning by operators using centralized operational control of flight operations;

c) use by flight crew members before departure; and

d) aircraft in flight.

9.1.2 Meteorological information supplied to operators and flight crew members shall cover the flightin respect of time, altitude and geographical extent. Accordingly, the information shall relate to appropriatefixed times, or periods of time, and shall extend to the aerodrome of intended landing, also covering themeteorological conditions expected between the aerodrome of intended landing and one alternate aerodromesdesignated by the operator. In addition, if agreed between the meteorological authority and the operator,information up to a further aerodrome shall be supplied.

9.1.3 Meteorological information, supplied to operators and flight crew members shall be up–to-dateand include any or all of the following information, as established by meteorological authority in consultationwith operators concerned:

a) forecasts of

1) upper winds and upper-air temperatures,

2) upper-air humidity;

3) altitude of flight levels;

4) tropopause altitude and temperature,

5) direction, speed and altitude of maximum wind; and


6) significant en-route weather SIGWX phenomena,

b) METAR and or SPECI (including trend forecasts as issued in accordance with regionalair navigation agreement), for the aerodromes of departure and intended landing, and fortake-off, en-route and destination alternate aerodromes;

c) TAF, or amended TAF for the aerodromes of departure and intended landing, and fortake-off, en-route and destination alternate aerodromes;

d) forecasts for take-off,

e) SIGMET information and those appropriate special air-reports not covered by a SIGMET,relevant to the whole route; and,

Note.— Appropriate special air-reports will be those not already used in preparation ofSIGMET.

f) subject to regional air navigation agreement, GAMET area forecasts and AIRMETinformation for low-level flights which are available at the meteorological office andwhich are relevant to the planned flight operations whole route.

WAFSOPSG 1/21 and1/22

9.1.4 Forecasts listed under 9.1.3 a) above shall be derived, to the extent possible as determined bythe meteorological authority concerned, from the digital forecasts provided by the WAFCs. Where forecastsare identified as being originated by the WAFCs, no modifications shall be made to their meteorologicalcontent. Charts derived from the digital forecasts provided by the WAFCs shall be made available, as aminimum, for fixed areas of coverage as shown in Figures A8-1, A8-2 and A8-3.

9.2.21.5 When forecasts of upper wind and upper-air information is temperature listed under 9.1.3a) 1) are supplied in chart form, it they shall consist of charts be fixed time prognostic charts for standard flightlevels. When forecasts of SIGWX phenomena listed under 9.1.3 a) 6) are supplied in chart form, they shall befixed time prognostic charts for an atmospheric layer limited by standard flight levels.

WAFSOPSG 1/1

9.2.39.1.6 Recommendation.—The forecasts of upper wind and upper-air temperature informationand the significant en route weather information of SIGWX phenomena requested for pre flight planning andin flight re-planning by the operator should shall be supplied as soon as it they becomes available, but not laterthan 3 hours before departure. Other meteorological information requested for pre flight planning and in flightre-planning by the operator should shall be supplied as soon as is practicable.

9.1.47 Where necessary, the meteorological authority of the State providing service for operators andflight crew members shall initiate coordinating action with the meteorological authorities of other States with

C-6 WAFSOPSG/2

a view to obtaining from them the reports and/ or forecasts required.

9.1.58 Meteorological information shall be supplied to operators and flight crew members at thelocation to be determined by the meteorological authority, after consultation with the operators and at the timeto be agreed upon between the meteorological office and the operator concerned. The service shall normallybe confined to flights originating within the territory of the State concerned, unless otherwise agreed betweenthe meteorological authority and the operator concerned. At an aerodrome without a meteorological office,arrangements for the supply of meteorological information shall be as agreed upon between the meteorologicalauthority and the operator concerned.

9.2 Information for operators for pre flightplanning and for in-flight re planningunder centralized operational control

9.2.1 Meteorological information for pre flight planning and in-flight re-planning by operators shallinclude any or all of the following information, as established by the meteorological authority in consultationwith operators concerned:

a) current and forecast: upper winds, upper air temperatures and humidity;

b) tropopause height and temperature, and direction, speed and height of maximum wind;

c) existing and expected significant en route weather phenomena and amendments thereto;

d) a forecast for take off;

e) METAR and, where available, SPECI (including trend forecasts) for the aerodrome ofdeparture, take-off and en-route alternate aerodromes, the aerodrome of intended landing anddestination alternate aerodromes, as determined by regional air navigation agreement;

f) TAF and amendments thereto for the aerodromes of departure and intended landing, and fortake-off, en-route and destination alternate aerodromes as determined by regional airnavigation agreement;

g) SIGMET information and appropriate special air-reports relevant to the whole of the routesconcerned as determined by regional air navigation agreement; and

Note.— Appropriate special air reports will be those not already used in preparation ofSIGMET messages.

h) AIRMET information for low-level flights as determined by regional air navigation agreement.

. . .


Editorial Note.— Renumber “9.3” to read “9.2”. In the note following the re-numbered 9.2, amend“9.5” to read “9.4”. In the re-numbered 9.2.2, amend “9.2.1” to read “9.1.3”.

9.43 Flight documentation

Note.— The requirements for the use of automated pre-flight information systems in providing flightdocumentation are given in 9.5.4.

9.43.1 Recommendation.— Flight documentation should shall cover the whole route to be flownand comprise information listed under 9.2.1.3 a) 1) and 6), b), c) and, e) to and, if appropriate, hf). However,in accordance with regional air navigation agreement, or in the absence thereof when where agreed betweenthe meteorological authority and operator concerned, flight documentation for flights of two hours' durationor less, after a short stop or turnaround should shall be limited to the information operationally needed, but inall cases the flight documentation should shall at least comprise information on 9.2.1.3 b), c), e), f), g) and, ifappropriate, hf).

9.4.2 Recommendation.— Meteorological offices should provide information received within theframework of the world area forecast system for flight documentation. The flight documentation should bepresented in the form of charts, tabular forms, or abbreviated plain-language texts. TAF should be presentedin accordance with the template in Appendix 5 or in abbreviated plain- language text using a tabularpresentation.

Note.— Models of charts and forms for use in the preparation of flight documentation are given inAppendix 1. These models and methods for their completion are developed by the World MeteorologicalOrganization on the basis of relevant operational requirements stated by the International Civil AviationOrganization.

9.4.33.2 Whenever it becomes apparent that the meteorological information to be included in theflight documentation will differ materially from that made available for pre flight planning and in flightre-planning, the operator shall be advised immediately and, if practicable, be supplied with the revisedinformation as agreed between the operator and the meteorological office concerned.

9.4.43.3 Recommendation.— Whenever necessary and possible, the flight documentation shouldbe brought up to date, in writing or orally, before it is supplied to flight crew members. In cases where a needfor amendment arises after the flight documentation has been supplied, and before take-off of the aircraft, themeteorological office should, as agreed locally, issue the necessary amendment or updated information to theoperator or to the local air traffic services unit, for transmission to the aircraft.

9.4.5 Recommendation.— The forms and charts included in flight documentation should be printedin English, French, Russian or Spanish; they should, wherever practicable, be completed in the languagerequested by the operator, preferably using one of those languages. Where appropriate, approved

C-8 WAFSOPSG/2

abbreviations should be used. The units employed for each element should be indicated; they should be inaccordance with Annex 5.

9.4.63.4 The meteorological authority shall retain information supplied to flight crew members, eitheras printed copies or in computer files, for a period of at least 30 days from the date of issue. This informationshall be made available, on request, for inquiries or investigations and, for these purposes, shall be retained untilthe inquiry or investigation is completed.

. . .

Editorial Note.— Renumber subsequent sections accordingly.

PART II

APPENDICES AND ATTACHMENTS

WAFSOPSG 1/1

APPENDIX 1. FLIGHT DOCUMENTATION — MODEL CHARTS AND FORMS

Editorial Note.— In Appendix 1, delete Model A, Example 1; amend Model A, Example 2 the title toread “OPMET information”and include examples of METAR, SPECI and SIGMET(WMO); delete Model TA, Example 2.

. . .

APPENDIX 2. TECHNICAL SPECIFICATIONS RELATEDTO WORLD AREA FORECAST SYSTEM AND METEOROLOGICAL OFFICES

(See Chapter 3 of this Annex.)

1. WORLD AREA FORECAST SYSTEM

1.1 Formats and codes

WAFCs shall adopt uniform formats and codes for the supply of forecasts and amendments.

1.2 Upper-air wind, temperature and humidity information forecasts

WAFSOPSG 1/28

1.2.1 The forecasts of upper winds; upper-air temperatures; and humidity; direction, speed and height


altitude of maximum winds; and tropopause heights altitude and temperatures, and altitude of flight levels shallbe prepared four times daily a day by a WAFC and shall be valid for fixed valid times at 6, 12, 18, 24, 30 and36 hours after the time (0000, 0600, 1200 and 1800 UTC) of the synoptic data on which the forecasts werebased and. The dissemination of forecasts shall be available for start of transmission in the above order andshall be completed as soon as technically feasible and not later than 6 hours after standard time of observation.

1.2.2 Recommendation.— The grid point forecasts prepared by a WAFC should shall comprise:

a) wind and temperature data for flight levels 50 (850 hPa), 100 (700 hPa), 140 (600 hPa), 180(500 hPa), 240 (400 hPa), 300 (300 hPa), 340 (250 hPa), 390 (200 hPa) and 450 (150 hPa);

b) tropopause height altitude and temperature, and;

c) direction, speed and height altitude of maximum wind;

cd) humidity data for flight levels 50 (850 hPa), 100 (700 hPa), 140 (600 hPa) and 180 (500 hPa);and

e) altitude data for flight levels 50 (850 hPa), 100 (700 hPa), 140 (600 hPa), 180 (500 hPa), 240(400 hPa), 300 (300 hPa), 340 (250 hPa), 390 (200 hPa) and 450 (150 hPa).

d) wind and temperature data for flight levels 530 (100 hPa) and 600 (70 hPa) when and whererequired.

WAFSOPSG 1/1

1.2.3 The foregoing grid point forecasts shall be issued by a WAFC in binary code form using theGRIB code form prescribed by WMO.

Note 1.— The GRIB code form is contained in WMO Publication No. 306, Manual on Codes,Volume I.2, Part B - Binary Codes.

Note 2.— WAFCs continue to issue forecasts of upper air wind and temperature in chart form inaccordance with regional air navigation plans until 1 July 2005.

1.2.4 The foregoing grid point forecasts shall be prepared by a WAFC in a fixed grid with ahorizontal resolution of 140 km.

Note.— 140 km represents a distance of about 1.25° of latitude.

1.3 Significant weather information (SIGWX) forecasts

1.3.1 General provisions

1.3.1.1 Forecasts of significant en-route weather phenomena shall be prepared by WAFCs shall be

C-10 WAFSOPSG/2

issued as significant weather (SIGWX) forecasts four times a day by a WAFC and shall be valid for fixed validtimes at 24 hours after the time ( of 0000, 0600, 1200 and 1800 UTC) of the synoptic data on which theforecasts were based. The transmission dissemination of each forecast shall be completed as soon as technicallyfeasible but at least not later than 12 hours before its validity after standard time of observation.

1.3.1.2 Forecasts of significant weather phenomena SIGWX forecasts shall be issued in binary codeform, using the BUFR code form prescribed by WMO.

Note 1.— The BUFR code form is contained in WMO Publication No. 306, Manual on Codes,Volume I.2, Part B — Binary Codes.

Note 2.— WAFCs continue to issue forecasts of significant weather in chart form in accordance withregional air navigation plans until 1 July 2005.

1.3.2 Types of SIGWX forecasts

1.3.3 Forecasts of significant weather phenomena SIGWX forecasts shall include all the items listedin Appendix 8, 4.3.1.1.The forecasts shall be issued for the following flight levels as:

a) high-level SIGWX forecasts for between flight levels between 250 to 630; and

b) medium-level SIGWX forecasts for between flight levels between 100 to 250 for limitedgeographical areas, as determined by regional air navigation agreement. If the averageelevation of the topography of the area could extend a significant topographical effect to flightlevel 100, a higher level should be specified for the base of the charts, in consultation with theWAFC concerned, and in accordance with regional air navigation agreement.

WAFSOPSG 1/19

Insert new text as follows:

1.3.3 Items included in SIGWX forecasts

High-level and medium-level SIGWX forecasts shall include the following items:

a) thunderstorms;

b) tropical cyclone;

c) severe squall lines;

d) moderate or severe turbulence (in cloud or clear air);


e) moderate or severe icing;

f) widespread sandstorm/duststorm;

g) cumulonimbus and towering cumulus clouds associated with a) to f) above;

h) tropopause altitude;

i) jetstreams;

IAVWOPSG 1/26

j) information on the location of volcanic eruptions which are producing ash clouds ofsignificance to aircraft operations, including those producing only steam, comprising: volcaniceruption symbol at the location of the volcano and, at the side of the chart, the volcanoeruption symbol, the name of the volcano, latitude/longitude, the date and time of firsteruption, if known, and a reference to SIGMETs and NOTAM or ASHTAM issued for the areaconcerned; and

WAFSOPSG 1/1

k) information on the location of an accidental release of radioactive materials into theatmosphere of significance to aircraft operations, comprising: the radioactivity symbol at thesite of the accident and, at the side of the chart, the radioactivity symbol, latitude/longitude ofthe site of the accident, date and time of the accident and a reminder to users to check NOTAMfor the area concerned.

Note.— Items to be included in low-level SIGWX forecasts (i.e. flight levels below 100) areincluded in Appendix 5.

1.3.4 Criteria for including items in SIGWX forecasts

The following criteria shall be applied for high-level and medium-level SIGWX forecasts:

a) items a) to g) in 1.3.3 shall only be included if expected to occur between the lower and upperlevel of the SIGWX forecast;

b) only those thunderstorms which warrant the issuance of a SIGMET as given in Appendix 6shall be indicated;

c) the abbreviations “CB” and “TCU” shall only be included where it refers to the occurrence orexpected occurrence of

1) an area of widespread cumulonimbus/towering cumulus clouds;

C-12 WAFSOPSG/2

2) cumulonimbus/towering cumulus clouds along a line with little or no space betweenindividual clouds; or

3) cumulonimbus/towering cumulus clouds embedded in cloud layers or concealed byhaze.

They shall not refer to isolated or scattered cumulonimbus/towering cumulus clouds notembedded in cloud layers or concealed by haze;

d) the inclusion of “CB” and “TCU” or the thunderstorm symbols shall be understood to includeall weather phenomena normally associated with cumulonimbus, towering cumulus clouds orthunderstorm, i.e. moderate or severe icing, moderate or severe turbulence and hail; and

e) where a volcanic eruption or the accidental release of radioactive materials into the atmospherewarrants the inclusion of the volcanic activity symbol or the radioactivity symbol in SIGWXforecasts, the symbols shall be included on high-level and medium-level SIGWX forecastsirrespective of the height to which the ash column or radioactive material is reported orexpected to reach.

End of new text.

WAFSOPSG 1/25

1.3.4 Recommendation. — Amendments to forecasts of significant weather phenomena should beissued with the minimum possible delay in accordance with the criteria in 1.4 and supplied in the form ofamended BUFR files.

1.4 Criteria for amendments to WAFS products

Recommendation. — WAFCs should apply the following criteria for the amendment of significanten-route weather forecasts:

SWH forecasts:turbulence, and occasional, frequent or embedded cumulonimbus

Newly expected occurrence or non-occurrence

SWM forecasts:aircraft icing, turbulence, cumulonimbus, and sandstorms/duststorms

Newly expected occurrence or non-occurrence

Volcanic eruptions or the accidental release of radioactive materials into the atmosphere, of significance toaircraft operations:


Inclusion or removal of volcanic activity symbol or radiation symbol.

WAFSOPSG 1/1

2. METEOROLOGICAL OFFICES

2.1 Use of WAFS products

2.1.1 The extent to which an aerodrome meteorological office prepares forecasts and/or makes useof products from WAFCs and other sources shall be determined by the meteorological authority concerned.

2.1.21 Recommendation.— Aerodrome meteorological offices should shall use output products of,to the extent possible as determined by the meteorological authority concerned, forecasts issued by the worldarea forecast system WAFCs in the preparation of flight documentation.

WAFSOPSG 1/22

2.1.32 In order to ensure uniformity and standardization of flight documentation, the WAFS GRIBand BUFR data received shall be decoded into standard WAFS charts in accordance with relevant provisionsin this Annex, and the meteorological content and identification of the originator of the WAFS forecasts shallnot be amended.

WAFSOPSG 1/25

2.2 Notification of WAFC concerningsignificant discrepancies

Meteorological offices using WAFS GRIB and/or BUFR data shall notify the WAFC concerned immediatelyif significant discrepancies in accordance with 1.4 the following criteria are detected or reported in respect ofWAFS data and products SIGWX forecasts:

a) icing, turbulence, thunderstorms which are obscured, frequent, embedded or occurring at asquall line, and sandstorms/duststorms:

— newly expected occurrence or non-occurrence; or

b) volcanic eruptions or the accidental release of radioactive materials into the atmosphere, ofsignificance to aircraft operations:

— inclusion or removal of volcanic activity symbol, or radiation symbol.

C-14 WAFSOPSG/2

The WAFC receiving the message shall acknowledge its receipt to the originator, together with a brief commenton the report and any action taken, using the same means of communication employed by the originator. If itis considered necessary to issue an amendment, an appropriate ADMIN message shall be transmitted to all usersthrough satellite broadcasts.

Note 1.— There is no requirement for meteorological offices to report incidents of radiologicalemergencies.

Note 2.— Guidance on reporting significant discrepancies is provided in the Manual of AeronauticalMeteorological Practice (Doc 8896).

WAFSOPSG 1/1

3. METEOROLOGICAL WATCH OFFICES

3.1 Use of WAFS products

The extent to which a meteorological watch office makes use of products from WAFCs and other sources shallbe determined by the meteorological authority concerned.

Editorial Note.— Renumber subsequent sections accordingly.

. . .

APPENDIX 5. TECHNICAL SPECIFICATIONS RELATED TO FORECASTS


Editorial Note.— Delete Section 4 in toto.; renumber “5.1” and “5.2” to read “4.1” and “4.2”.

Insert new text as follows:

4.3 Content of area forecasts for low-level flights in chart form

4.3.1 When chart form is used for area forecasts for low-level flights, the forecast of upper wind andupper-air temperature shall be issued for points separated by no more than 500 km (300 NM) and for at leastthe following altitudes: 600, 1 500 and 3 000 m (2 000, 5 000 and 10 000 ft).

4.3.2 When chart form is used for area forecasts for low-level flights, the forecast of SIGWX


phenomena shall be issued as low-level SIGWX forecast for flight levels up to 100 (or up to flight level 150in mountainous areas, or higher, where necessary). Low-level SIGWX forecasts shall include the followingitems:

a) the phenomena warranting the issuance of a SIGMET as given in Appendix 6 and which areexpected to affect low-level flights; and

b) the elements included in area forecasts for low-level flights as given in 5.1 except elements r)and u) concerning upper winds and upper-air temperatures and forecast lowest QNH,respectively.

Note.— Guidance on the use of terms "ISOL", "OCNL" and "FRQ" referring to cumulonimbusand towering cumulus clouds, and thunderstorms is given in Appendix 6.

Editorial Note.— Renumber “5.3” to read “4.4”.

End of new text.

APPENDIX 8. TECHNICAL SPECIFICATIONS RELATED TO SERVICE FOR OPERATORS AND FLIGHT CREW MEMBERS


. . .

2. SPECIFICATIONS RELATED TOINFORMATION FOR PRE-FLIGHT PLANNING

AND IN-FLIGHT RE-PLANNING

. . .

2.3 Specific needs of supersonic aircraft

Recommendation.— Meteorological information for preflight planning and in-flight re-planning byoperators for supersonic aircraft should include data covering the levels used for transonic and supersonicflight, together with the levels that may be used for subsonic flight. Particular mention should be made ofoccurrence and expected occurrence, location and vertical extent of cumulonimbus clouds, turbulence andprecipitation.

2.43 Specific needs of helicopter operations

C-16 WAFSOPSG/2

Recommendation.— Meteorological information for preflight planning and in-flight re-planning byoperators of helicopters flying to offshore structures should include data covering the layers from sea level toflight level 100. Particular mention should be made of the expected surface visibility, the amount, type (whereavailable), base and tops of cloud below flight level 100, sea state and sea surface temperature, mean sea-levelpressure, and the occurrence and expected occurrence of turbulence and icing, as determined by regional airnavigation agreement.

3. SPECIFICATIONS RELATED TOBRIEFING AND CONSULTATION

3.1 Specific needs of supersonic aircraft

Recommendation.— Briefing and/or consultation for flight crew members of supersonic aircraftshould include meteorological information covering the flight levels of transonic and supersonic flight.Particular mention should be made of occurrence and expected occurrence, location and vertical extent ofcumulonimbus clouds, turbulence and precipitation.

3.2 Specific needs of low-level flights

Recommendation.— Briefing and/or consultation for low-level flights, including those in accordancewith the visual flight rules, should include meteorological information covering altitudes up to flight level 100(or up to flight level 150 in mountainous areas or higher, where necessary). Particular mention should be madeof the occurrence or expected occurrence of any phenomena causing widespread reduction of visibility to lessthan 5 000 m, as well as the occurrence or expected occurrence of clouds which may affect the flight.

3.31 Information required to be displayed

3.31.1 To assist the flight crew members and others concerned with the preparation of the flight andfor use in briefing and consultation, the meteorological office shall display the latest available:

a) METAR and or SPECI (including trend forecasts as issued in accordance with regional airnavigation agreement);

b) TAF and trend forecasts or amended TAF;

c) aerodrome warnings relating to the local aerodrome;

d) forecasts for take-off;

e) GAMET area forecast;

ef) SIGMET and AIRMET information and special air-reports not covered by a SIGMET;

fg) current and prognostic charts;


gh) meteorological satellite images or mosaics and/or nephanalyses; and

hi) ground-based weather radar information.

3.31.2 Recommendation.— The material displayed should be readily accessible to the flight crewmembers or other flight operations personnel concerned. By agreement between the meteorological authorityand the user, the display may be used in lieu of briefing and/or consultation.

4. SPECIFICATIONS RELATED TOFLIGHT DOCUMENTATION

4.1 General Presentation of information

4.1.1 The flight documentation related to forecasts of upper wind and upper-air temperature andSIGWX phenomena shall be presented in the form of charts. For low-level flights, alternatively, GAMET areaforecasts shall be used.

Note.— Models of charts and forms for use in the preparation of flight documentation are given inAppendix 1. These models and methods for their completion are developed by the World MeteorologicalOrganization on the basis of relevant operational requirements stated by the International Civil AviationOrganization.

4.1.2 METAR and SPECI (including trend forecasts as issued in accordance with regional airnavigation agreement), TAF, GAMET, SIGMET and AIRMET shall be presented in accordance with thetemplates in Appendices 3, 5 and 6, respectively. METAR, SPECI, TAF, GAMET, SIGMET and AIRMETreceived from other meteorological offices shall be included in flight documentation without change.

Note.— Examples of the form of presentation of METAR/SPECI and TAF are given in Appendix 1.

4.1.3 Recommendation. The location indicators and the abbreviations used should be explainedin the flight documentation.

4.1.4 Recommendation.— The forms and the legend of charts included in flight documentationshould be printed in English, French, Russian or Spanish. Where appropriate, approved abbreviations shouldbe used. The units employed for each element should be indicated; they should be in accordance with Annex5.

4.2 Charts in flight documentation

4.12.1 Presentation of flight documentation Characteristics of charts

C-18 WAFSOPSG/2

4.12.1.1 Recommendation.— Charts included in flight documentation should have a high standardof clarity and legibility and should have the following physical characteristics:

a) for convenience, the largest size of charts should be about 42 × 30 cm (standard size A3) andthe smallest size should be about 21 × 30 cm (standard size A4). The choice between thesesizes should depend on the route lengths and the amount of detail that needs to be given in thecharts as agreed between meteorological authorities and users;

b) major geographical features, such as coastlines, major rivers and lakes should be depicted ina way that makes them easily recognizable;

c) for charts prepared by computer, meteorological data should take preference over basic chartinformation, the former cancelling the latter wherever they overlap;

d) major aerodromes should be shown as a dot and identified by the first letter of the name of thecity the aerodrome serves as given in Table AOP of the relevant regional air navigation plan;

e) a geographical grid should be shown with meridians and parallels represented by dotted linesat each 10° latitude and longitude; dots should be spaced one degree apart;

f) latitude and longitude values should be indicated at various points throughout the charts (i.e.not only at the edges); and

g) labels on the charts for flight documentation should be clear and simple and should presentthe name of the world area forecast centre or, for non-WAFS products, the originating centre,the type of chart, date and valid time and, if necessary, the types of units used in anunambiguous way.

4.12.1.2 Recommendation.— Meteorological information included in flight documentation shouldshall be represented as follows:

a) winds on charts should shall be depicted by arrows with feathers and shaded pennants on asufficiently dense grid;

b) temperatures should shall be depicted by figures on a sufficiently dense grid;

c) wind and temperature data selected from the data sets received from a world area forecastcentre should shall be depicted in a sufficiently dense latitude/longitude grid; and

d) wind arrows should shall take precedence over temperatures and either should shall takeprecedence over chart background.

4.12.1.3 Recommendation.— For short-haul flights charts should be prepared covering limitedareas at a scale of 1:15 × 106 as required and subject to regional air navigation agreement.

4.12.2 Set of charts to be provided


4.12.2.1 Recommendation.— The minimum number of charts for flights between flight level 250and flight level 630 should shall include a high-level significant weather SIGWX chart (flight level 250 to flightlevel 630) and a forecast 250 hPa wind and temperature chart. The actual charts provided for pre-flight andin-flight planning and for flight documentation should shall be as agreed between meteorological authoritiesand other users within a service area concerned.

4.12.2.2 Recommendation.— The set of charts Charts to be provided shall be derived, to the extentpossible as determined by the meteorological authority concerned, from the digital forecasts provided by underthe world area forecast system WAFCs for flights below flight level 250 should be as agreed between userStates and other users.

4.12.3 Height indications

Recommendation.— In flight documentation height indications should shall be given as follows:

a) all references to en-route meteorological conditions, such as height indications of upper winds,turbulence or bases and tops of clouds, should shall preferably be expressed in flight levels;they may also be expressed in pressure, altitude or, for low-level flights, height above groundlevel; and

b) all references to aerodrome meteorological conditions, such as height indications of the basesof clouds, should shall be expressed in height above the aerodrome elevation.

Editorial Note.— Delete Sections 4.2; 4.3 and 4.4.

4.53 Specifications related to low-level flights

4.53.1 In chart form

Recommendation.— Where the forecasts are supplied in chart form, flight documentation forlow-level flights, including those in accordance with the visual flight rules, operating up to flight level 100 (orup to flight level 150 in mountainous areas or higher, where necessary), should contain the following asappropriate to the flight:

a) information from relevant SIGMET and AIRMET messages;

b) upper wind and upper-air temperature charts as given in 4.2.1.2 above Appendix 5, 4.3.1; and

c) significant weather charts as given in 4.3.1.3 above Appendix 5, 4.3.2.

C-20 WAFSOPSG/2

4.53.2 In abbreviated plain language

Recommendation.— Where the forecasts are not supplied in chart form, flight documentation forlow-level flights, including those in accordance with the visual flight rules, operating up to flight level 100 (upto flight level 150 in mountainous areas or higher, where necessary), should contain the following informationas appropriate to the flight:

a) SIGMET and AIRMET information; and

b) information included in the area forecasts for low-level flights as given in Appendix 5 or,where the forecasts are issued in the form of an abbreviated plain-language text, the GAMETarea forecasts.

Note.— An example of the GAMET area forecast is given in Appendix 5.

. . .

6. SPECIFICATIONS RELATED TOINFORMATION FOR AIRCRAFT IN FLIGHT

. . .

6.2 Information for in-flight planningby the operator

Recommendation.— Meteorological information for planning by the operator for aircraft in flightshould be supplied during the period of the flight and should normally consist of any or all of the following:

a) meteorological reports, METAR and SPECI (including trend forecasts as issued in accordancewith regional air navigation agreement);

b) TAF and landing forecasts amended TAF;

bc) SIGMET and AIRMET information and special air-reports relevant to the flight, unless thelatter have been the subject of a SIGMET message; and

cd) upper wind and upper-air temperature information.

6.3 Information for supersonic flights

Recommendation.— For supersonic aircraft in flight the meteorological office serving the aerodromeof intended landing should, on request by the operator, supply a forecast covering the transonic decelerationand subsonic descent phases. This forecast should be transmitted to the area control centre or flightinformation centre concerned within the two hours before arrival. The operator should advise themeteorological office, in good time, of the location of the descent path and of the time at which the aircraft is


expected to commence the descent.

Editorial Note.— Insert FASID Charts MET 4, 5 and 6; renumber them as Figures A8-1, A8-2 andA8-3.

— — — — — — — —

Appendix D to the Report D-1

APPENDIX D






PART I — Core SARPs

. . .

CHAPTER 3. WORLD AREA FORECAST SYSTEMAND METEOROLOGICAL OFFICES

. . .

3.2 World area forecast centres

. . .

3.2.2 In case of interruption of the operation of a WAFC, its functions shall be carried out by theother WAFC.

Note. — Back-up procedures to be used in case of interruption of the operation of a WAFC are givenin Attachment C. Back-up procedures are expected to be subject to minor revisions updated by the World AreaForecast System Operations Group (WAFSOPSG) as necessary and the latest revision can be found at theWAFSOPSG website at: www.icao.int/anb/wafsopsg.

. . .

Editorial Note.— Delete Attachment C in toto.

— — — — — — — —

Appendix E to the Report E-1

APPENDIX E






PART II


. . .




. . .

1.3 Significant weather information

. . .

Editorial Note.— Under new Section 1.3.4, Criteria for including items in SIGWX forecasts(Appendix C refers), insert a new sub-item f) as follows:

f) in the case of co-incident or the partial overlapping of items b), j) and k) in 1.3.3, the highest priorityshall be given to item j), followed by item k) and b). The item with the highest priority shall be placedat the location of the event, and an arrow shall be used to link the location of the other item(s) to itsassociated symbol or text box.

— — — — — — — —

Appendix F to the Report F-1

APPENDIX F

PROPOSED DESCRIPTION FOR OUTPUT PRODUCTS FOR

TURBULENCE, ICING AND CB/TCU CLOUDS

1) For each forecast validity time, a field of average icing potential and a field of maximum icingpotential will be provided for each of the layers 750 to 650 hPa, 650 to 550 hPa, 550 to450 hPa, 450 to 350 hPa and 350 to 250 hPa. A value indicating that an icing potential indexcannot be defined will be assigned to grid-boxes occupied by terrain;

2) For each forecast validity time, a field of average in-cloud turbulence (ICT) potential and afield of maximum ICT potential will be provided for each of the layers 750 to 650 hPa, 650to 550 hPa, 550 to 450 hPa, 450 to 350 hPa and 350 to 250 hPa. A value indicating that an ICTpotential index cannot be defined will be assigned to grid-boxes occupied by terrain. Thesefields will contain information on turbulence associated with large-scale cloud layers;

3) For each forecast validity time, a field of average clear-air turbulence (CAT) potential and afield of maximum CAT potential will be provided for each of the levels 400, 300, 250, 200 and150 hPa. These fields will contain information on turbulence associated with wind shear andmountain waves;

4) The prototype CB product will provide information on the horizontal and vertical extent ofconvective clouds with tops colder than -20<C. For each forecast validity time five fields willbe provided indicating:

— the maximum percentage of the area of a grid-point forecast to be occupied by CBsat any level in the vertical. A value of 0 will be assigned to grid-boxes containing noCBs, 1 to grid-boxes with a maximum CB cover of between 1 and 50 per centinclusive, 2 to boxes with a maximum CB cover of between 51 and 75 per centinclusive and 3 to boxes with a maximum CB cover of greater than 75 per cent;

— the pressure altitude at the base of any CBs in each grid-box;

— the pressure altitude at the top of any CBs in each grid-box;

— the pressure altitude at the base of the lowest layer of cloud in which CBs areembedded in each grid-box; and

— the pressure altitude at the top of the highest layer of cloud in which CBs areembedded in each grid-box.

F-2 WAFSOPSG/2

The pressure altitudes will be expressed in hPa and metres (feet), and will be calculated usingthe ICAO Standard Atmosphere. A value indicating that a pressure altitude cannot be defined will be assignedto grid-boxes in the CB pressure altitude and embedded CB pressure altitude fields not forecast to contain CBsor embedded CBs, respectively.

— — — — — — — —

Appendix G to the Report G-1

APPENDIX G






PART II


. . .




. . .

1.3 Significant weather information

. . .

Editorial Note.— Under new paragraph 1.3.1.1 (Appendix C refers), amend “not later than 12hours” to read “not later than 11 hours”.

— — — — — — — —

Appendix H to the Report H-1

APPENDIX H

WORK PROGRAMME OF THE WAFSOPSG

1. Terms of reference

The WAFSOPSG should:

a) provide advice and guidance to the WAFC Provider States concerning the operation of theWAFS and its effectiveness in meeting current global and, where appropriate, regionaloperational requirements;

b) develop proposals for the development of the WAFS in order to ensure that it continues tomeet evolving global and, where appropriate, regional operational requirements;

Note.— Such proposals for requirements should be made under ICAO procedures for theamendment of Annex 3.

c) monitor, assess and provide advice on technological developments relevant to the WAFS toensure that full advantage may be taken of such technologies to maintain and, where possible,improve the cost-effectiveness of the WAFS, and develop appropriate proposals, as necessary,for the adoption of such technologies;

d) liaise with the MET advisory groups to the PIRGs regarding progress by States in theircapability to receive/decode/process WAFS output products in the GRIB and BUFR codeforms, and any other binary codes that may be used in the WAFS in the future. Based oninformation received, provide advice as necessary to ICAO, and through ICAO to WMO,regarding training and/or guidance material that may be required to ensure that all States havethe opportunity to use WAFS output products regardless of the present or future mode ofcoding and/or transmission;

e) advise the WAFCs in the development and use of appropriate WAFS output performanceindicators;

f) monitor the WAFS output to ensure that both the appearance of the output and location ofsystems in areas of overlap are harmonized;

g) liaise with the SADISOPSG and the MET advisory groups to the PIRGs regarding the globaldistribution of WAFS data and products by satellite broadcast; and

h) make regular progress reports to the Air Navigation Commission.

H-2 WAFSOPSG/2

2. Work programme

The WAFSOPSG should:Updated: 5/3/04

ANC TaskNo.

Work Programme Item Source and(references in

brackets)

Estimatedcompletion date

Note on progress

MET-8202 1) oversee the implementation andoperation of the WAFS; develop relatedSARPs and guidance material

ANC 161-12(WAFSOPSG 1/3)

ongoing Management report to beprepared by the WAFCs ateach WAFSOPSGmeeting.

MET-8202 2) review the requirements need foradditional maximum improvements inspatial and temporal resolution of windlevels forecasts (and the possibility ofindicating vertical wind profiles near jet-streams)

ANC 129-21;NAT SPG 40/4;(WAFSSG/3, 5.6.2;WAFSSG/7, 5.2.2;WAFSOPSG 1/13;WAFSOPSG 2/14)

2010(Amendment 75)

assessment by IATApresented at theWAFSOPSG/2.

MET-8202 3) develop quantitative airframe icingintensity criteria (including objective“icing index”) to be used, inter alia, inautomated SIGWX forecasts

ANC 127-17;(WAFSSG/3, 8.6;WAFSOPSG 1/15;WAFSOPSG 2/15)

2010(Amendment 75)

progress report to bepresented by the WAFCsat the WAFSOPSG/3.

MET-8202 4) study the feasibility (and advisability) ofamending increasing the lead time forissuance of SIGWX forecasts to 16hours

MET Div. (2002)Rec. 1/4;ANC 161-12(WAFSOPSG 1/18;WAFSOPSG 2/17and 2/18)

2010(Amendment 75)

lead time to be increasedto 13 hours in Amendment74; feasibility of issuanceof SIGWX forecasts up to17 hr before their validitytime to be assessed by theWAFCs in time for theWAFSOPSG/3.

MET-8202 5) develop improved forecast algorithms(and WAFS output products) for icingmaking use of improved modelresolution

MET Div. (2002)Rec. 1/10;ANC 161-12(WAFSOPSG 1/16;WAFSOPSG 2/16)

2010(Amendment 75)

progress report presentedat the WAFSOPSG/2; report on operational trialsexpected at theWAFSOPSG/3; work tobe completed by theWAFSOPSG/4.

MET-8202 6) study the suppression of the requirementto indicate cloud types other than CBand TCU in SWM forecasts

ANC 146-12(WAFSOPSG 1/19;WAFSOPSG 2/3)

2007(Amendment 74)

proposal (including thecloud cover) reviewed bythe WAFSOPSG/2;included in draftAmendment 74.

MET-8202 7) develop guidelines for generatingWAFS charts from the GRIB and BUFRcoded data

WAFSOPSG 1/21and 1/22(WAFSOPSG 2/3)

2007(Amendment 74)

proposal reviewed by theWAFSOPSG/2; includedin draft Amendment 74.

MET-8202 8) eliminate the need for issuingamendments to WAFS SIGWX forecasts

WAFSOPSG 1/25(WAFSOPSG 2/3)

2007(Amendment 74)


Appendix H to the Report H-3

ANC TaskNo.

Work Programme Item Source and(references in

brackets)

Estimatedcompletion date

Note on progress

MET-8202 9) optimize the future requirement forWAFS SWM forecasts


2010(Amendment 75)

proposal to replace SWMforecasts by new WAFSoutput products endorsedby the WAFSOPSG/2.

MET-8202 10) consider the migration to the GRIB2code form

WAFSOPSG 1/27and 1/22(WAFSOPSG 2/20)

2010(Amendment 75)

migration plan in time forthe WAFSOPSG/3

MET-8202 11) introduce forecasts of height aboveground level of the altitude ofstandard WAFS flight levels


2007(Amendment 74)


MET-9101 12) develop procedures for the qualitycontrol of meteorologicalinformation included in the ADSmessages, including the ways andmeans of providing the necessaryfeed-back to the operatorsconcerned


2010(Amendment 75)

assessment of thefeasibility of providingfeed-back to be completedby the WAFSOPSG/3.

MET-9801 13) develop improved forecastalgorithms and WAFS outputproducts for turbulence, makingmaximum use of the global EDRdata and improved model resolution,for direct operational use in WAFSSIGWX forecasts


2010(Amendment 75)

progress report presentedat the WAFSOPSG/2; report on operational trialsexpected at theWAFSOPSG/3; work tobe completed by theWAFSOPSG/4.

— END —

Documents

INTERNATIONAL CIVIL AVIATION ORGANIZATION · 2012-01-09 · INTERNATIONAL CIVIL AVIATION ORGANIZATION. ... That, the WAFS-related regi onal procedures in all basic ANPs/FASIDs as