ZCZC SPCSWOMCD ALL
ACUS11 KWNS 200324 
SPC MCD 200324 
TXZ000-200430-

MESOSCALE DISCUSSION 0288
NWS STORM PREDICTION CENTER NORMAN OK
1024 PM CDT TUE MAR 19 2013

AREAS AFFECTED...CNTRL THROUGH SERN TX

CONCERNING...SEVERE THUNDERSTORM WATCH 56...

VALID 200324Z - 200430Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 56
CONTINUES.

SUMMARY...THERE IS STILL A LOW THREAT OF SVR HAIL...PARTICULARLY IN
AND AROUND LLANO COUNTY...BUT OVERALL...THE SVR WEATHER THREAT
ACROSS WW 56 IS BECOMING INCREASINGLY MARGINAL.

DISCUSSION...REGIONAL RADAR IMAGERY INDICATES A WEAKENING TREND WITH
MUCH OF THE ONGOING ACTIVITY ACROSS CNTRL TX. SPECIAL SOUNDING FROM
CLL DEPICTS AN INVERSION BETWEEN 400-500 MB /LIKELY ASSOCIATED WITH
THE PACIFIC AIRMASS MOVING INTO THE REGION/ ATOP THE EML /FROM
APPROXIMATELY 800 TO 500 MB/. THIS INVERSION IS LIMITING INSTABILITY
AND RESULTANT UPDRAFT STRENGTH...PRECLUDING MOST STORMS FROM
REACHING SVR THRESHOLDS. A FEW STRONG STORMS REMAIN ACROSS SAN
SABA...LLANO...AND BURNET COUNTIES WHERE SOME MUCAPE REMAINS BUT THE
CELLS ACROSS N-CNTRL TX CONTINUE TO WEAKEN. AS THE SHORTWAVE TROUGH
CONTINUES EWD...MID-LEVEL COOLING WILL LIKELY REMOVE THE INVERSION
BUT THIS PROCESS WILL BE OFFSET BY COOLING AND DRYING
LOW-LEVELS...FURTHER LIMITING SVR POTENTIAL. 

AS SUCH...THE SVR THREAT ACROSS WW 56 IS BECOMING INCREASINGLY
MARGINAL ALTHOUGH ISOLATED SVR HAIL CANNOT BE COMPLETELY RULED
OUT...PARTICULARLY ACROSS THE WRN TX HILL COUNTRY WHERE COOLING
TEMPERATURES ALOFT MAY PROMOTE A BRIEF PERIOD OF INCREASED MUCAPE
BEFORE LOW-LEVEL THETA-E DECREASES.

..MOSIER.. 03/20/2013

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

ATTN...WFO...HGX...FWD...EWX...SJT...

LAT...LON   29699714 29819814 30109934 30319943 30679946 30999933
            31219915 31389892 31569861 31849799 32099700 32029630
            31889579 31549554 31099548 30679554 30069581 29759671
            29699714 

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