ZCZC SPCSWOMCD ALL
ACUS11 KWNS 210919 
SPC MCD 210919 
TXZ000-211045-

MESOSCALE DISCUSSION 0183
NWS STORM PREDICTION CENTER NORMAN OK
0319 AM CST THU FEB 21 2013

AREAS AFFECTED...PARTS OF CENTRAL TX INCLUDING PARTS OF THE HILL
COUNTRY AND EDWARDS PLATEAU

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 210919Z - 211045Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...AN INCREASE IN CONVECTION ACROSS PARTS OF CENTRAL TX
SUGGESTS THAT TORNADO POTENTIAL -- WHILE LOW ATTM -- COULD INCREASE
OVER THE NEXT HOUR OR SO.

DISCUSSION...LATEST RADAR LOOP SLOWS A LINE OF STORMS STEADILY
INCREASING WITH TIME ACROSS PARTS OF CENTRAL TX -- WITH THIS LINE
CROSSING SJT /SAN ANGELO TX/ ATTM.  THE STORMS ARE DEVELOPING
PERPENDICULAR TO A WARM FRONT WHICH BISECTS THE DEVELOPING LINE --
RUNNING FROM JUST S OF SJT ESEWD TO JUST S OF CLL /COLLEGE STATION/.

WITH A FAIRLY MOIST /LOW 60S DEWPOINTS/ BOUNDARY LAYER WITHIN THE
WARM SECTOR SOUTH OF THE FRONT...AND MIXED-LAYER CAPE NEAR 1000
J/KG...POTENTIAL FOR CONTINUED CONVECTIVE INCREASE SEEMS
POSSIBLE...AS THE UPPER SYSTEM CONTINUES TO ADVANCE TOWARD THIS
REGION INCREASING BACKGROUND ASCENT.

GIVEN THE WARM-ADVECTION TYPE WIND PROFILE EVIDENT ACROSS THE
AREA...WITH SSELY BOUNDARY LAYER FLOW VEERING/INCREASING WITH HEIGHT
TO 50 KT FROM THE SW AT AROUND 1.5 KM AGL...SHEAR IS SUPPORTIVE OF
SUPERCELLS INCLUDING LOW-LEVEL ROTATION.  

WHILE CONVECTION-ALLOWING HIGH-RES MODELS DO NOT DEPICT SUBSTANTIAL
CONVECTIVE DEVELOPMENT BEYOND WHAT IS CURRENTLY REVEALED BY
RADAR...THIS AREA IS BEING CLOSELY MONITORED -- GIVEN THE BACKGROUND
ENVIRONMENT -- FOR SIGNS OF STORM ORGANIZATION WHICH WOULD THEN
WARRANT TORNADO WATCH ISSUANCE.

..GOSS.. 02/21/2013

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

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

LAT...LON   30139973 30210076 31790015 31389865 30659850 30169908
            30139973 

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