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 091956
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0156 PM CST WED JAN 09 2013
   
   VALID 092000Z - 101200Z
   
   ...NO SVR TSTM AREAS FORECAST...
   
   THE ONLY CHANGE TO THE OUTLOOK AT 20Z IS TO REMOVE PART OF THE 5
   PERCENT WIND DAMAGE AND 2 PERCENT TORNADO PROBABILITIES ALONG THE
   MIDDLE TX COAST. THIS AREA IS BEHIND CONVECTION THAT IS MOVING INTO
   FAR SE TX. THE SEVERE THREAT SHOULD CONTINUE THROUGH THE LATE
   AFTERNOON ACROSS FAR SE TX AND FAR SW LA WHERE INSTABILITY IS VERY
   WEAK BUT DEEP LAYER SHEAR COULD BE STRONG ENOUGH FOR A MARGINAL
   SEVERE THREAT.
   
   ..BROYLES.. 01/09/2013
   
   .PREV DISCUSSION... /ISSUED 1008 AM CST WED JAN 09 2013/
   
   ...SYNOPSIS...
   
   A POLAR BRANCH SHORT-WAVE TROUGH OVER THE FAR NERN PACIFIC WILL
   ADVANCE INTO THE PACIFIC NW AND CA THIS PERIOD...AMPLIFYING WITH
   TIME OWING TO THE EQUATORWARD PROGRESSION OF MID TO UPPER-LEVEL JET
   STREAKS INTO THE BASE OF THE PARENT TROUGH.  THESE DEVELOPMENTS WILL
   LEAD TO THE NWD ACCELERATION OF A SUBTROPICAL BRANCH UPPER LOW FROM
   NRN MEXICO INTO W-CNTRL TX.  THIS LATTER SYSTEM WILL BE ATTENDED BY
   A 50-70 KT MIDLEVEL JET STREAK WHICH WILL OVERSPREAD THE ERN HALF OF
   TX NWD THROUGH THE RED RIVER VALLEY.
   
   IN THE LOW LEVELS...A SURFACE LOW ANALYZED ALONG THE TX COAST NEAR
   PSX AS OF 16Z WILL DEVELOP NWWD INTO THE TX HILL COUNTRY BY
   10/00Z...AND INTO NWRN TX BY THE END OF THE D1 PERIOD.  MEANWHILE...
   A WARM FRONT --DELINEATING CP AND MODIFIED CP AIR MASSES-- CURRENTLY
   FROM THE LOW NEWD THROUGH E-CNTRL TX AND CNTRL LA WILL LIFT SLOWLY
   NWD.  A SECONDARY WARM FRONT --WHICH DEMARCATES THE MODIFIED CP AIR
   FROM THAT OF TRUE MARITIME ORIGIN-- IS EXPECTED TO REMAIN ALONG THE
   SHELF WATERS OF THE NRN GOM.  FINALLY...A COLD FRONT WILL ADVANCE
   EWD ALONG THE TX COAST TOWARD THE LOWER SABINE RIVER VALLEY.  
   
   ...MIDDLE/UPPER TX COAST INTO SWRN LA...
   
   AS OF MID-MORNING...A PRE-FRONTAL CONVECTIVE BAND EXISTED FROM NEAR
   CLL SWD INTO THE NWRN GOM APPROXIMATELY 50-80 NM E OF BRO.  THIS
   ACTIVITY DEFINES THE SRN PORTION OF THE WARM CONVEYOR BELT OF THE
   SUBTROPICAL BRANCH SYNOPTIC SYSTEM...WITH A BROAD ZONE OF ISENTROPIC
   ASCENT AND DCVA AHEAD OF THE PARENT UPPER LOW LIKELY BEING THE
   PRIMARY PROCESSES FORCING THIS ACTIVITY.  LATEST CONVECTION-ALLOWING
   AND MESOSCALE MODEL GUIDANCE ARE IN RELATIVELY GOOD AGREEMENT IN
   SUGGESTING A GRADUAL EWD PROGRESSION OF THIS CONVECTIVE BAND INTO
   THE LOWER SABINE RIVER VALLEY BY TONIGHT AS THE PARENT UPPER LOW
   BEGINS TO LIFT NWD TOWARD THE RED RIVER VALLEY.  
   
   AS MENTIONED ABOVE...IT APPEARS THAT THE SRN-MOST WARM FRONT WHICH
   DELIMITS THE NRN EXTENT OF A HIGH THETA-E...MT AIR MASS WILL REMAIN
   OFFSHORE THROUGH THE PERIOD.  THIS COUPLED WITH WIDESPREAD CLOUDS
   AND PRECIPITATION WILL LIMIT AIR MASS DESTABILIZATION ALONG THE
   COASTAL PLAINS OF TX INTO SWRN LA. THIS IS CONFIRMED BY
   MODEL-DERIVED FORECAST SOUNDINGS WHICH SHOW THE MAINTENANCE OF A
   SHALLOW...NEAR-SURFACE STABLE LAYER AND MLCAPE VALUES GENERALLY LESS
   THAN 500 J/KG.  THUS...DESPITE MODESTLY STRONG LOW-LEVEL AND
   DEEP-LAYER SHEAR WHICH WILL PERSIST ACROSS THE REGION...THE OVERALL
   SETUP DOES NOT APPEAR TO WARRANT ANY MORE THAN LOW TORNADO AND
   DAMAGING WIND PROBABILITIES.
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z