Categorical Graphic
Probabilistic Tornado Graphic
Probability of a tornado within 25 miles of a point. Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point.
Probabilistic Damaging Wind Graphic
Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point. Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point.
Probabilistic Large Hail Graphic
Probability of hail 1" or larger within 25 miles of a point. Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point.

   SPC AC 200553
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1253 AM CDT FRI APR 20 2012
   
   VALID 201200Z - 211200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF SRN TX...
   
   ...SYNOPSIS...
   
   FULL LATITUDE BUT PROGRESSIVE UPPER TROUGH WILL CONTINUE TO AMPLIFY
   AND MOVE THROUGH THE MS VALLEY...GREAT LAKES AND SRN PLAINS FRIDAY
   PRECEDED BY A COLD FRONT. THIS BOUNDARY WILL STRETCH FROM A SFC LOW
   OVER THE GREAT LAKES SWWD INTO SWRN TX 12Z FRIDAY AND CONTINUE TO
   ADVANCE EWD AND SEWD. BY 12Z SATURDAY THE FRONT WILL EXTEND FROM THE
   NERN STATES SWWD INTO THE WRN GULF.
   
   ...SOUTH THROUGH SERN TX...
   
   NEAR SFC DEWPOINTS IN THE UPPER 50S-LOW 60S HAVE ADVECTED INTO SRN
   TX BENEATH PLUME OF STEEPER LAPSE RATES. THE ATMOSPHERE WILL
   DESTABILIZE FURTHER AS DIABATIC HEATING COMMENCES...AND MLCAPE FROM
   1500-2000 J/KG WILL LIKELY DEVELOP IN THIS REGION DURING THE DAY.
   PRE-FRONTAL WARM SECTOR WILL LIKELY REMAIN CAPPED TO SFC BASED
   STORMS DUE TO PRESENCE OF A WARM EML ALREADY IN PLACE. WITH UPPER
   TROUGH AXIS LAGGING BEHIND THE FRONT...SUFFICIENT INSTABILITY AND
   DEEP FORCING SHOULD EXIST IN POST FRONTAL ZONE TO INITIATE STORMS.
   EFFECTIVE SHEAR OF 40-45 KT WILL PROMOTE A POTENTIAL FOR ORGANIZED
   STORMS INCLUDING SUPERCELLS AND BOWING SEGMENTS WITH ISOLATED
   DAMAGING WIND AND LARGE HAIL POSSIBLE INTO EARLY EVENING.
   
   ...OH VALLEY AREA...
   
   MOISTURE AND INSTABILITY WILL BE MORE LIMITED ALONG NEWD EXTENSION
   OF THE FRONT INTO THE OH VALLEY. AS A RESULT THE SEVERE THREAT IN
   THIS REGION IS EXPECTED TO REMAIN MORE LIMITED. A FEW STORMS WILL
   LIKELY DEVELOP ALONG FRONT OR IN POST FRONTAL REGION WHERE STRONGER
   SHEAR WILL RESIDE. A MARGINAL THREAT WILL EXIST FOR ISOLATED STRONG
   WIND GUSTS AS ACTIVITY DEVELOPS EWD...BUT COVERAGE OF ANY SEVERE
   EVENTS IF THEY OCCUR AT ALL IS EXPECTED TO REMAIN SPARSE.
   
   ..DIAL/SMITH.. 04/20/2012
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z