Snowfall Analysis at Snowfall Analysis at FGFFGF

using Snoopy and ArcGISusing Snoopy and ArcGIS

Mike LukesMike LukesNWS Service HydrologistNWS Service Hydrologist

WFO Eastern North DakotaWFO Eastern North DakotaGrand Forks, ND Grand Forks, ND

Snowfall Reports to Graphic Snowfall Reports to Graphic AnalysisAnalysis

Collect 1, 2, or 3-Day Snowfall Amounts Collect 1, 2, or 3-Day Snowfall Amounts from the Hydro DataBase (IHFS).from the Hydro DataBase (IHFS).

Transfer Snowfall Data from AWIPS to Transfer Snowfall Data from AWIPS to PC-based ArcGIS host.PC-based ArcGIS host.

Use ArcMap and Spatial Analyst to make Use ArcMap and Spatial Analyst to make a raster Snowfall analysis graphic.a raster Snowfall analysis graphic.

SNOOPYSNOOPYAWIPS IHFS database “snooper”AWIPS IHFS database “snooper”

Developed by Mike Callahan, SH @ WFO Developed by Mike Callahan, SH @ WFO Louisville, Ky. (Available from LAD).Louisville, Ky. (Available from LAD).

Graphical Interface to IHFS database.Graphical Interface to IHFS database. Interactively runs SQL queries, saves Interactively runs SQL queries, saves

results in electronic files.results in electronic files. Use INFORMIX flavor of SQL.Use INFORMIX flavor of SQL. Plan to use Mike’s Pref – preformater Plan to use Mike’s Pref – preformater

utility - in the near future.utility - in the near future.

SQL QueriesSQL Queries

1, 2, 3, 4-day Snowfall Analysis1, 2, 3, 4-day Snowfall Analysis

2-day Snow Depth Analysis2-day Snow Depth Analysis

Snow Water AnalysisSnow Water Analysis

Other uses include AWOS 00z/12z precip Other uses include AWOS 00z/12z precip amounts.amounts.

2-day Snowfall SQL Querry2-day Snowfall SQL Querryselect * from snow sselect * from snow swhere s.obstime =where s.obstime =(select max(obstime) from snow (select max(obstime) from snow where lid = s.lid and s.pe=‘SF’ where lid = s.lid and s.pe=‘SF’ and date(obstime) = today)and date(obstime) = today)and s.value>0and s.value>0order by 1 into tem tsf1;order by 1 into tem tsf1;

select * from snow sselect * from snow swhere s.obstime =where s.obstime =(select max(obstime) from snow (select max(obstime) from snow where lid = s.lid and s.pe=‘SF’ where lid = s.lid and s.pe=‘SF’ and date(obstime) = today-1)and date(obstime) = today-1)and s.value>0and s.value>0order by 1 into tem tsf1;order by 1 into tem tsf1;

select lid, value, obstime from tsf1select lid, value, obstime from tsf1unionunionselect lid, value, obstime from tsf2select lid, value, obstime from tsf2order by 1 into temp tsft;order by 1 into temp tsft;

select lid, count, (*) num, select lid, count, (*) num, sum(value) tot from tsftsum(value) tot from tsftgroup by lidgroup by lidorder by tot desc into tsff;order by tot desc into tsff;

select t.lid nwsli, round(t.tot,1) tot,select t.lid nwsli, round(t.tot,1) tot,round(l.lat,3) lat, round(l.lon,3)*-1 lon,round(l.lat,3) lat, round(l.lon,3)*-1 lon,t.Num numt.Num numfrom tsff t, location lfrom tsff t, location lwhere t.lid=l.lidwhere t.lid=l.lidorder by 2 desc;order by 2 desc;

GNU gFTP clientGNU gFTP client xfer Snow Analysis File to PCxfer Snow Analysis File to PC

FGF uses the Linux gFTP utility to xfer the FGF uses the Linux gFTP utility to xfer the Snow Analysis SQL results file to samba Snow Analysis SQL results file to samba mapped network drivemapped network drive

Results file is accessible to ArcGIS on a Results file is accessible to ArcGIS on a local LAN PC.local LAN PC.

NWS CRH has a number of “floating NWS CRH has a number of “floating licenses” for ArcGIS and Spatial Analyst licenses” for ArcGIS and Spatial Analyst which the region’s WFOs can use locally.which the region’s WFOs can use locally.

Pref may be able to bypass gFTP step.Pref may be able to bypass gFTP step.

Snow Amounts in ArcGISSnow Amounts in ArcGIS plotted on FGF HSA County Backgroundplotted on FGF HSA County Background

Results file contains NWSLI, Snowfall Results file contains NWSLI, Snowfall Amount, Lat, Lon, and # of daily obs.Amount, Lat, Lon, and # of daily obs.

Snow Amounts are plotted (add XY data Snow Amounts are plotted (add XY data from tools menu) on HSA county from tools menu) on HSA county background.background.

NWSLIs can be also plotted for NWSLIs can be also plotted for geographical orientation.geographical orientation.

Spatial AnalystSpatial AnalystSnow AnalysisSnow Analysis

Interpolated to Raster using:Interpolated to Raster using: Inverse Distance WeightingInverse Distance Weighting Spline…???Spline…??? Kriging…???Kriging…???

• ArcUser Magazine Jul-Sep 04 “Interpolating ArcUser Magazine Jul-Sep 04 “Interpolating Surfaces in ArcGIS Spatial Analyst”Surfaces in ArcGIS Spatial Analyst”

To do: Compare spline and kriging to IDW To do: Compare spline and kriging to IDW for a better analysis.for a better analysis.

Contouring and Time StampingContouring and Time Stamping

Spatial Analyst – Surface Analysis – Spatial Analyst – Surface Analysis – Contour function.Contour function. Specify contour intervals.Specify contour intervals.

Day/Time Stamp VB add-on.Day/Time Stamp VB add-on. DateElement icon put on toolbar.DateElement icon put on toolbar. Available from ESRI web page.Available from ESRI web page.

ImprovementsImprovementsnotes, ideas and limitationsnotes, ideas and limitations

Use Pref for SQL query and file xfer Use Pref for SQL query and file xfer (RRM?)(RRM?)

Snow Obs from buffer countiesSnow Obs from buffer counties Improve boundary conditions for better analysis near Improve boundary conditions for better analysis near

bordersborders Can serve as 1Can serve as 1stst guess for subjective analysis guess for subjective analysis Compare to sat pixCompare to sat pix IDW not good fit to natural snowfall patternsIDW not good fit to natural snowfall patterns

Kriging?Kriging? Easier process to send to graphic to webEasier process to send to graphic to web