[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 240747
SWOMCD
SPC MCD 240747 
TXZ000-240915-

MESOSCALE DISCUSSION 0227
NWS STORM PREDICTION CENTER NORMAN OK
0147 AM CST THU FEB 24 2005

AREAS AFFECTED...PORTIONS S TX

CONCERNING...SEVERE THUNDERSTORM WATCH 37...

VALID 240747Z - 240915Z

LINE OF STRONG-SEVERE TSTMS SHOULD CONTINUE MOVING EWD AND ESEWD
ACROSS PORTIONS SAT METRO AREA SWD TO NEAR COT...WITH POTENTIAL FOR
DAMAGING WIND AND LARGE HAIL.  WW SHOULD BE MAINTAINED ALONG AND E
OF THIS LINE THROUGH SCHEDULED EXPIRATION...UNLESS REPLACEMENT WW IS
REQUIRED.  ANOTHER WW MAY BE NEEDED BEFORE SCHEDULED 9Z EXPIRATION
OF WW 37...TO COVER AREAS FROM NEAR CRP WWD AND NWD.

CONVECTIVE LINE APPEARS TO BE BACKBUILDING SWD ACROSS DIMMIT COUNTY
INTO ENVIRONMENT CHARACTERIZED BY FAVORABLE BUOYANCY...BUT MORE
MARGINAL VERTICAL SHEAR WITH SWD EXTENT.  MODIFIED 00Z RAOBS AND RUC
FCST SOUNDINGS INDICATE SHALLOW...DIABATICALLY COOLED STABLE LAYER
NEAR SFC...BENEATH ELEVATED MUCAPE OF APPROXIMATELY 2500 J/KG. VWP
AND RUC DATA INDICATES 500 MB FLOW 30-35 KT AROUND LATITUDE OF
SAT...DECREASING TO 15-20 KT ALONG CRP-LRD LINE.  THIS SUPPORTS BOTH
WEAKENING LOW-MIDLEVEL SHEAR AND WEAKENING MIDLEVEL SR FLOW SWD
THROUGH REGION.  THEREFORE ANY SUPERCELLULAR STRUCTURES SUCH AS
THOSE RECENTLY OBSERVED ALONG SRN END OF TSTM BAND OVER ZAVALA/FRIO
COUNTIES...SHOULD EVOLVE QUICKLY THROUGH HEAVY-PRECIP PHASE WITH
POTENTIAL FOR SMALL BOW ECHO DEVELOPMENT.  GREATEST ASSOCIATED
DAMAGING WIND POTENTIAL APPEARS TO EXTEND ACROSS ATASCOSA...EXTREME
SRN BEXAR...KARNES AND WILSON COUNTIES.  THIS IS ALSO ALONG AND JUST
S OF QUASISTATIONARY SFC BAROCLINIC ZONE..WHERE NEAR-SFC STABLE
LAYER IS RELATIVELY SHALLOW AND MOST CONDUCIVE TO PENETRATION OF
DOWNDRAFT GUSTS TO SFC.

..EDWARDS.. 02/24/2005

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

ATTN...WFO...CRP...EWX...SJT...HGX...

30250166 30409823 28669824 28500168 

29989821 29989767 29849689 29619669 29289668 28889671
28409695 27989734 27949826 28069908 28199934 28329944
28469943 28619928 28669824 

WWWW