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Anvil Lightning and Aircraft. Briefing to DC3 Participants by Stephanie Weiss 9 April 2012. Types of lightning-aircraft interaction ( Rakov and Uman 2003, pp. 347-348). Corona discharge Aircraft-intercepted lightning Aircraft-initiated lightning. - PowerPoint PPT Presentation
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Anvil Lightning and Aircraft
Briefing to DC3 Participantsby Stephanie Weiss9 April 2012Anvil Lightning and AircraftTypes of lightning-aircraft interaction (Rakov and Uman 2003, pp. 347-348)Corona dischargeAircraft-intercepted lightningAircraft-initiated lightningAnvil Lightning StudyWeiss et al. (MWR in press 2012)Extension of work by Kuhlman et al. (GRL - 2009)Anvil lightning: Lightning > 30km from the 30dBZ contour in the storm coreAnvil lightning in six supercell thunderstormsStorm IDAnalysis Time (UTC)No. of anvil flashesAnvil flash rate (min-1)Average anvil flash size (km2)24 May 2004 N2210-2330270.37143524-25 May 2004 S2220-0020940.81115426 May 20042230-2340110.16232029 May 2004 N2250-232060.50177929-30 May 2004 S2250-00103222.684014-5 June 20052250-0020160.212340
Visualization of Lightning Mapping Array (LMA) Data
Colors represent time sequence of VHF sources (a,b,d,e) Time-height plot (a) Plan view (d) Projection views (b,e) Histogram (c)
abdce
26 May 2004 Isolated supercell2235:00 2324:30 UTCTable of Anvil FlashesStorm IDAnalysis Time (UTC)No. of anvil flashesAnvil flash rate (min-1)Average anvil flash size (km2)24 May 2004 N2210-2330270.37143524-25 May 2004 S2220-0020940.81115426 May 20042230-2340110.16232029 May 2004 N2250-232060.50177929-30 May 2004 S2250-00103222.684014-5 June 20052250-0020160.212340
29-30 May 2004 Two supercells one dying and one intensifying2311 0017 UTCFlash Initiation in Anvil: Anvil Interaction
2321:45 UTC 29 May 2004 CAPPI at 7kmAnvil-Initiated where anvils interact: 2321:458Flash Initiation in Anvil: Anvil Interaction
2321:45 UTC 29 May 2004Anvil of Northern StormAnvil of Southern StormShow that CG and initiation location in flash from previous slide is in between the two anvils, with no development underneath the anvil.9
24 May 2004 Line of supercells2227 2300 UTC24 May 2004 Secondary reflectivity maximaLightning being initiated in these cellsFlash Initiation in Anvil: Reflectivity Maximum
2328:43 UTC 24 May 2004Ground Flashes beneath Anvil: Rain or Virga
2324:30 UTC 24 May 2004+CG: 8.7kA13Screening Layer ChargeDifference in conductivity between clear and cloudy airDiscontinuity in current across the cloud surfacesCharge on the surface of the cloud boundaryCloud boundary vs Radar echo boundary?Aircraft in LMA Data: Aircraft-Initiated Example2259-2305 UTC on 24 May 2004Aircraft-Initiated, Bidirectional DischargesSingle-point, Corona Discharges850 km/hr, 525 mi/hr16Aircraft in LMA Data: Aircraft-Initiated Example2259-2305 UTC on 24 May 2004
KVNX Base Reflectivity from 2301:36 UTC on 24 May 2004
Lightning: 2305-2310 UTC
KVNX Base Reflectivity from 2301:36 UTC on 24 May 2004
Lightning: 2305-2310 UTC5 km10 km15 km
KVNX CAPPI at 10 km from 2301:36 UTC on 24 May 2004
Lightning: 2305-2310 UTCDiscussion JumpstartWatch for:Anvils from more than one storm interactingSecondary cells of reflectivity forming in the anvilVirga and/or rain beneath the anvilWill a general rule of keeping the aircraft >30km downstream of recent lightning activity work?
26 May 2004 Isolated supercell2235:00 2324:30 UTC
29-30 May 2004 Two supercells one dying and one intensifying2311 0017 UTC
24 May 2004 Line of supercells2227 2300 UTC
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(i) 2346 UTC
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(h) 2339 UTC40
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(f) 2333 UTC60
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(e) 2333 UTC
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(d) 2326 UTC60
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(c) 2326 UTC
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(b) 2320 UTC60
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(a) 2320 UTC
Reflectivity Factor (dBZ)
77.
5 7
5.0
72.
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5 6
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62.
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Reflectivity Factor (dBZ)
7
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70503010
86420
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604020 0 80Distance (km)
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70503010
86420
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604020 0 80Distance (km)
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50-50
Dist
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N (k
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Distance East of KOUN (km)
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Distance East of KOUN (km)100500-50
86420
141210
(b)
-140 -120 -100 -80 -60 -40 -20 0East-West distance (km)
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20040524
22:59:40 23:01:20 23:03:00 23:04:40 23:06:205
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0 33006600990005
1015
252579 pts
alt-histogram dz= 200m
/Users/sweiss/Out/OK_20040524_225859_230600_noNLDN.eps - Fri Jan 21 17:08:12 2011
-40 -20 0 20East-West distance (km)
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1015
8006 pts
alt-histogram dz= 200m
/Users/sweiss/Out/OK_20040524_225910_230456_mzoom.eps - Fri Jan 21 17:17:02 2011