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 301601
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1101 AM CDT SAT APR 30 2011
   
   VALID 301630Z - 011200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF N TX AND THE
   ARKLATEX INTO THE LWR OH/LWR MS VLYS...
   
   RAPID INTENSIFICATION OCCURRED IN NRN PORTION OF LARGE SCALE TROUGH
   MOVING ACROSS WRN U.S. OVERNIGHT. AT 12Z A STACKED LOW WAS OVER WRN
   ND WHILE THE SRN PORTION OF THE WRN TROUGH TRAILS BACK LEADING TO
   ANOTHER UPPER LOW FORMING NEAR THE FOUR CORNERS TONIGHT.
   
   STRONG COLD FRONT AT 16Z EXTEND SWD THRU MKC THEN ACROSS CENTRAL OK
   TO SWRN TX.  FRONT WILL SLOW ITS SWD PROGRESS THIS AFTERNOON AND
   EVENTUALLY STALL AS AN E/W BOUNDARY FROM SRN AR TO NEAR THE TX BIG
   BEND BY 12Z SUN AS UPPER FLOW BACKS AHEAD OF SRN ROCKIES TROUGH AND
   DEVELOPING UPPER LOW.
   
   IMPRESSIVE MOISTURE RETURN UNDER WAY ACROSS ERN TX INTO LOWER MS
   VALLEY UNDER INITIALLY A VERY STRONG CAP.
   
   ...ARKLATEX TO LWR MS/LWR OH VLYS...
   MOISTURE SHOULD CONTINUE TO SPREAD NEWD ACROSS MUCH OF AR AND PARTS
   OF THE LWR MS VLY THROUGH EARLY SUN...AHEAD OF
   AFOREMENTIONED COLD FRONT.
   
   EML CAP AND WEAK LARGE SCALE FORCING FOR ASCENT EXPECTED TO PRECLUDE
   SFC-BASED TSTM DEVELOPMENT OVER SLIGHT
   RISK AREA THROUGH MUCH OF THE AFTERNOON. STORMS
   SHOULD...HOWEVER...FORM BY LATE AFTN OR EARLY EVE FROM NE TX INTO
   CNTRL AR AS FRONT ENCOUNTERS MOISTURE RETURN AND SFC HEATING FURTHER
   DESTABILIZES THE REGION.  WITH TIME...STORMS SHOULD SPREAD NEWD INTO
   SE MO AND WRN KY/TN...WHILE REGENERATIVE ACTIVITY PERSISTS OVER THE
   ARKLATEX.
   
   AMPLE /2500-3000 J PER KG/ SBCAPE WILL BE PRESENT FOR SUSTAINED
   STORMS/SUPERCELLS THROUGH AT LEAST MID EVE GIVEN 50-60 KT WSWLY MID
   LVL FLOW ATOP 35-40 KT SSWLY LLJ.  BY THIS EVENING NEAR SURFACE
   BASED STORMS SHOULD  EVOLVE INTO CLUSTERS/LINES POSING A THREAT FOR
   LARGE HAIL AND DMGG WINDS NEWD INTO SE MO/WRN KY AND WRN TN.  THE
   POTENTIAL ALSO WILL EXIST FOR A COUPLE TORNADOES...ESPECIALLY FROM
   NE TX ENEWD INTO ERN AR FROM EARLY TO MID EVE.
   
   INCREASING UPR DIFFLUENCE DOWNSTREAM FROM DEVELOPING FOUR CORNERS
   UPR LOW...DEEP AND INCREASINGLY MOIST SWLY LOW TO MID LVL FLOW...AND
   STALLING OF SFC FRONT SUGGEST LIKELIHOOD FOR ADDITIONAL
   REGENERATIVE/BACK-BUILDING STORMS OVER THE ARKLATEX REGION THROUGH
   LATE TONIGHT...WITH A THREAT FOR HEAVY RAIN IN ADDITION TO A
   DIMINISHING THREAT FOR SVR HAIL/WIND.  ELEVATED STORMS ALSO MAY FORM
   WWD OVER PARTS OF THE RED RVR VLY REGION LATE TONIGHT/EARLY SUN AS
   SSWLY LLJ STRENGTHENS ABOVE STALLING FRONT.  THIS ACTIVITY COULD
   PRODUCE SVR HAIL.
   
   ..HALES/HURLBUT.. 04/30/2011
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z