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
   
   
   ATTN...WFO...FWD...EWX...SJT...
   
   LAT...LON   30139973 30210076 31790015 31389865 30659850 30169908
               30139973