[MCD] SWOMCD

Wed Apr 26 00:34:58 UTC 2006

ACUS11 KWNS 260032
SWOMCD
SPC MCD 260031 
TXZ000-260200-

MESOSCALE DISCUSSION 0658
NWS STORM PREDICTION CENTER NORMAN OK
0731 PM CDT TUE APR 25 2006

AREAS AFFECTED...S-CNTRL/SERN TX

CONCERNING...SEVERE THUNDERSTORM WATCH 249...

VALID 260031Z - 260200Z

SUPERCELLS CAPABLE OF PRODUCING LARGE HAIL WILL CONTINUE ACROSS SWRN
PORTION OF WATCH. ADDITIONAL DEVELOPMENT IS LIKELY FURTHER NEWD IN
THE NEXT FEW HOURS. CONTINUE WW.

AN UNSTABLE ENVIRONMENT EXISTS ACROSS PORTIONS OF S-CNTRL TX WITH
MLCAPES OF 2500 TO 3500 J/KG /PER 00Z CRP SOUNDING/. SUPERCELLS WILL
CONTINUE TO THRIVE FOR THE NEXT FEW HOURS FROM AROUND KARNES TO JIM
WELLS COUNTIES. ADDITIONAL DEVELOPMENT TO THE W OF THESE AREAS
SUGGESTS A TRANSITION TO A MORE MULTICELLULAR MODE MAY OCCUR AFTER
DARK. IMPRESSIVE SWD MOVING SUPERCELL ACROSS SRN DUVAL COUNTY WOULD
APPEAR TO HAVE SOME TORNADIC POTENTIAL GIVEN MOVEMENT. HOWEVER...A
VERY WEAK LOW-LEVEL WIND FIELD PER 00Z CRP SOUNDING AND INCREASING
BOUNDARY LAYER STABILIZATION WILL TEND TO MITIGATE THIS THREAT.

FURTHER NE...TIMING OF CONVECTIVE DEVELOPMENT IS STILL UNCERTAIN.
00Z LCH SOUNDING AND MODIFIED RUC SOUNDINGS SUGGEST THE AREA IS
UNCAPPED. CELLS ARE BEGINNING TO INITIATE IN LAVACA COUNTY AND
ADDITIONAL DOWNSTREAM DEVELOPMENT APPEARS LIKELY WITHIN THE NEXT FEW
HOURS. 18Z NAM-WRF GUIDANCE INDICATED THE LOW-LEVEL MOISTURE
CONVERGENCE ALONG THE COLD FRONT WILL STRENGTHEN BETWEEN 00 AND 03Z.
THE ENVIRONMENT IS UNSTABLE WITH AROUND 2500 J/KG MLCAPE PER 00Z LCH
SOUNDING. ALTHOUGH SHEAR IS RATHER WEAK...THE DEGREE OF INSTABILITY
WILL SUPPORT A LARGE HAIL THREAT.

..GRAMS.. 04/26/2006

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

ATTN...WFO...LCH...HGX...CRP...EWX...BRO...

28290026 28990041 29069958 29029872 29359756 30219652
31139492 30349466 29699439 29339433 28669530 27639721
27309783 27289887 27289932 

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