[MCD] SWOMCD

[Mesoscale Convective Discussions]

ACUS11 KWNS 260238
SWOMCD
SPC MCD 260238 
TXZ000-260415-

MESOSCALE DISCUSSION 0661
NWS STORM PREDICTION CENTER NORMAN OK
0938 PM CDT TUE APR 25 2006

AREAS AFFECTED...FAR SRN TX

CONCERNING...SEVERE THUNDERSTORM WATCH 252...

VALID 260238Z - 260415Z

THREAT FOR SVR STORMS WILL LIKELY BE CONFINED TO AREAS ALONG THE
LOWER RIO GRANDE RIVER VALLEY THROUGH THE NEXT FEW HRS WITH A MORE
LIMITED THREAT ALONG THE IMMEDIATE FAR SOUTH TX COAST. GIVEN
PRESENCE OF LARGE SCALE DIFFLUENT FLOW PATTERN ALOFT...CONVECTION
WILL LIKELY CONTINUE WELL BEYOND WW 252 EXPIRATION TIME /04Z/.
TRENDS WILL BE MONITORED...BUT A NEW WW IS NOT ANTICIPATED AFTER
04Z...ALTHOUGH LOCAL WFO EXTENSION OF WW 252 MAY OCCUR.

00Z BRO SOUNDINGS SHOWED A PRONOUNCED WARM LAYER CENTERED AROUND 850
MB...WITH TEMPERATURES 3-4 DEGREES WARMER IN THIS LAYER THAN ON THE
00Z CRP SOUNDING. RECENT RADAR TRENDS INDICATE THAT THIS LARGE AMT
OF CINH WILL LIKELY KEEP THE ORGANIZED SVR THREAT WEST OF THE
IMMEDIATE FAR SOUTH TX COAST. VERY HIGH INSTABILITY AND MODEST SHEAR
WILL CONTINUE TO FAVOR SVR HAIL/WIND WITH THE STRONGEST STORMS OVER
THE LOWER RIO GRANDE RIVER VALLEY AWAY FROM THE COAST. LOW LEVEL
SHEAR HAS INCREASED RECENTLY PER THE BRO 88-D VWP DATA...AND THUS AN
ISOLATED TORNADO THREAT WILL ALSO REMAIN POSSIBLE /ESPECIALLY WITH
THE SUPERCELL STORM OVER ERN JIM HOGG AND WRN BROOKS COUNTIES/.
ADDITIONAL SVR STORMS MAY CONTINUE TO DEVELOP ALONG THE SFC
FRONT/OUTFLOW BOUNDARY INTERSECTION OVER THE NWRN 1/3RD OF WW 252
FOR THE NEXT SEVERAL HRS WHERE LOW LEVEL CONVERGENCE WILL BE
MAXIMIZED.

..CROSBIE.. 04/26/2006

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...CRP...BRO...

25839955 27539957 27309685 25569686 

WWWW