24 May 2002 WCR & KA data VPDD: Low SSP up: 19:10 Z @ 2000 m AGL: dryline below 19:14 Z descending from 2000 m to 1500 m AGL: intercept the cold front in a 180 degree turn. Cold front is 16 km to the WNW of dryline 19:18 Z @ 1500 m AGL: dryline below 19:29 Z @ 900 m AGL: dryline below 19:32 Z @ 900 m AGL: cold front, 14 km to the WNW of dryline Low SSP up: 19:35 Z @ 360 m AGL: cold front and dryline, separated some 11 km (10 km at corrspndg angle) 19:49 Z @ 170 m AGL: cold front and dryline, separated by 3-4 km 20:00 Z @ 2300 m AGL: cold front and dryline, separated by 1-2 km 20:09 Z @ 2300 m AGL: cold front and dryline collapsed (wind synthesized) 20:25 Z @ 1200 m AGL 20:28 Z @ 170 m AGL: cold front has surged under the dryline 20:46 Z @ 170 m AGL; cold front has surged under the dryline 20:54 Z @ 1200 m AGL 21:11 Z @ 2400 m AGL: cold front, about 9 km behind deep-convective initiation (estimated frontal speed relative to dryline : 6-7 m/s)

19:10 Z Moist side sounding: cold front 16 km dryline Ground ~650 m high Clouds between 1200-2100 m AGL

nadir beam ESE 110 19:10:09- 19:11:20 WSW 290 dryline Time match correct

19:14 Z cold front Cold front Cold front SE NW SE NW 19:13:48 19:15:22 nadir beam

19:18 Z Flight level: ~1500 m AGL Wind shift

Ahead of cold front, in the dry sector?? Dryline? Moist air nadir beam WSW 290 Dryline? Time match correct ESE 110 cold front?

19:29-19:32 Z cold front dryline

cold frontal surface @900 m dry sector thermal ?? dryline cold frontal surface @900 m foreward beam!!! WSW 290 14 km ESE 110 Moist air Cold air

Low SSP up 360 m 360 m 170 m cold front @ 360m 170 m @ 19:35 @ 19:49 dryline @ 170m @ 19:48 cold front cold front dryline dryline

UWKA 19:33 19:52 19:43

cold front q q NW 315 SE 135 Height above frontal motion flight level flight level: 360 m AGL total length: 11.2 km aspect ratio: 1:1 Relative humidity cold front Mixing ratio superplot,193320,193530,xvars=['mrlaf','rh','thetad','thetae'],radarch='hh',ngraphs=3,/timeax,/transpose,/landsc,/timein,color=41 q q e

cold front SE NW NW 315 SE 135 frontal motion kft km Height above flt level total length: 5.9 km flight level: 360 m AGL NW SE convergence! ascent

cold frontal surface @360 m frontal motion SE 135 NW 315 cold frontal surface @360 m u m/s v m/s

cold frontal surface @360 m dryline 11 km Time matched OK v m/s westerly southerly northerly u m/s

Attenuated??

superplot_old,194600,195030,xvars=['mrlaf','trf','thetad','thetae'],radarch='hh',ngraphs=3,/timeax,/transpose,/landsc,/timein,color=41,wcr_avg=9,/no_AR

20:00 Z VPDD Flight level: ~2300 m AGL

WNW 290 ESE 110 frontal motion 19:59:08-20:02:38 front Dryline? Moist air WNW 290 ESE 110

20:10 Z VPDD Flight level: ~2300 m AGL cold front below @ 20:09 Z

SSE 164 NNW 344 frontal motion front & dryline moist air cold air Time match OK

dBZ Height below flight level (m) Time (UTC) WCR nadir antenna reflectivity Flight level: 2300 m AGL dBZ Aspect ratio : 2:1

20:25 Z VPDD Flight level: ~1200 m AGL cold front below @ 20:25 Z descending to 170 m

WNW 344 ESE 164 km possibly stratus clouds frontal motion 20:21:50-20:25:40 WNW 344 front ESE 164

cold front @ 170m @ 20:46 cold front @ 170m @ 20:28

-5 SSE 164 frontal motion NNW 344 km dBZ 6 8 -45 Total length: 11.7 km, flight level: 170 m

km vertical velocity NW 300 SE 120 frontal motion SE 120 Total length: 11.7 km, flight level: 170 m vertical velocity

20:54 Z VPDD Flight level: ~1200 m AGL cold front below around 20:54 Z ascending from 170 m

ESE 110 WNW 290 frontal motion 20:51:58-20:56:28 Embryo of a Cb cell that develops here in the next 15 min? WNW 290 Dry air above the cold front Not sure about time match Moist air ahead of dryline If the air ahead of the sharp gradient is drier and warmer, why does it seem to have a cloud at flight level?

21:11 Z VPDD Flight level: ~2400 m AGL Last leg First cumulonimbus formation (~21:12:30) cold front below around 21:11 Z (ascending after this time)

21:06:36-21:13:20 WNW 290 Gravity waves in the cold-frontal stratus? Questionable (dixit Sam) frontal motion ESE 110 This is a cloud whose towering tops had grown well above 4 km AGL, part of a line of storm cells aligned with the cold front 9 km Deep convection develops 9 km ahead of sfc cold front

UWKA AMA 21:05 21:15