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 301234
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0734 AM CDT WED MAY 30 2012
   
   VALID 301300Z - 311200Z
   
   ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON INTO TONIGHT
   ACROSS PART OF SWRN KS...WRN/CNTRL OK... AND FAR NRN TX...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CNTRL HIGH PLAINS INTO
   THE OZARK PLATEAU AND SRN PLAINS...
   
   --POTENTIALLY SIGNIFICANT SEVERE WEATHER EPISODE ACROSS PARTS OF THE
   CNTRL/SRN PLAINS THIS AFTERNOON INTO TONIGHT--
   
   ...SYNOPSIS...
   
   POLAR BRANCH SHORT-WAVE TROUGH OVER THE NRN HIGH PLAINS WILL
   PROGRESS SEWD AND PHASE WITH LOWER-LATITUDE IMPULSES EMERGING FROM
   THE CNTRL/SRN PLAINS TO SUPPORT BROADER-SCALE TROUGH AMPLIFICATION
   FROM THE UPPER MS VALLEY INTO OZARK PLATEAU AND SRN PLAINS BY
   31/12Z.  THIS UPPER-AIR PATTERN EVOLUTION WILL RESULT IN THE EWD
   DEVELOPMENT AND/OR RE-FORMATION OF A SURFACE LOW FROM NWRN TX INTO
   THE OZARKS BY LATE TONIGHT/EARLY THU.  AS THIS OCCURS...A COLD FRONT
   MOVING SEWD THROUGH THE NRN/CNTRL PLAINS WILL MERGE WITH A
   STATIONARY FRONT SITUATED OVER SRN KS/NRN OK INTO THE OZARK PLATEAU
   WITH THE COMPOSITE BOUNDARY --LIKELY AIDED BY CONVECTIVE OUTFLOW--
   SURGING SEWD INTO THE SRN PLAINS.
   
   ...CNTRL/SRN PLAINS...
   
   12Z SURFACE OBSERVATIONS SHOW THAT A CONVECTIVE OUTFLOW ASSOCIATED
   WITH DECAYING MCS OVER N-CNTRL/NERN TX EXTENDS FROM NEAR LFK NWWD
   THROUGH ACT TO A SURFACE LOW N OF LBB.  VAD DATA FROM FREDRICK OK
   AND OK MESONET OBSERVATIONS INDICATE THAT THIS BOUNDARY IS QUITE
   SHALLOW OVER SWRN OK/NWRN TX WHERE SURFACE WINDS HAVE ALREADY VEERED
   TO A SELY DIRECTION.  AND WHILE DEWPOINTS HAVE DROPPED INTO THE
   UPPER 50S AT MANY LOCATIONS ACROSS THE WRN HALF OF OK...INCREASED
   BOUNDARY LAYER MIXING WILL LIKELY RESULT IN VALUES INCREASING INTO
   THE LOW/MID 60S LATER TODAY.  AT THE SAME TIME...A PLUME OF VERY
   STEEP MIDLEVEL LAPSE RATES /I.E. 8.5-9.5 C PER KM/ WILL OVERSPREAD
   WARM SECTOR AND CONTRIBUTE TO A MODERATE-STRONGLY UNSTABLE AIR MASS
   BY AFTERNOON WITH MLCAPE RANGING FROM 1000-1500 J/KG IN SWRN NEB TO
   AS HIGH AS 3000-4000 J/KG ACROSS PARTS OF WRN OK.
   
   CONSIDERABLE VARIABILITY EXISTS AMONGST MESOSCALE AND
   CONVECTION-ALLOWING MODEL GUIDANCE WITH REGARD TO SPECIFIC DETAILS
   OF CONVECTIVE EVOLUTION THIS AFTERNOON INTO EVENING.  CURRENT
   THINKING IS THAT THE PREFERRED CORRIDOR FOR STORM INITIATION WILL BE
   ACROSS WRN PARTS OF KS/OK BY MID AFTERNOON WHERE LARGE-SCALE FORCING
   FOR ASCENT PROGRESSIVELY OVERSPREADS WRN/NWRN EXTENSION OF WARM
   SECTOR.  FORECAST HODOGRAPHS INDICATE VERTICALLY VEERING WIND
   PROFILES /MOST NOTABLY ACROSS WRN KS/ WITH 45-55 KT OF EFFECTIVE
   BULK SHEAR WHICH WILL SUPPORT RAPID SUPERCELL EVOLUTION.  
   
   VERY LARGE HAIL AND A FEW TORNADOES WILL BE POSSIBLE WITH THE
   INITIAL STORMS BEFORE ACTIVITY GROWS UPSCALE INTO ONE OR MORE
   FORWARD-PROPAGATING MCSS.  LARGE-SCALE PATTERN IS ANALOGOUS TO PAST
   CNTRL/SRN PLAINS DERECHO EVENTS...AND A SIMILAR TYPE SCENARIO MAY
   UNFOLD THIS EVENING INTO TONIGHT WITH THE POTENTIAL FOR WIDESPREAD
   DAMAGING WINDS FROM PARTS OF SRN KS THROUGH WRN/CNTRL OK INTO NRN
   TX.
     
   ...SERN TX/LA TO THE CNTRL GULF COAST...
   
   OUTFLOW BOUNDARY ASSOCIATED WITH DECAYING N-CNTRL/NERN TX MCS WILL
   LIKE FOCUS RENEWED TSTM DEVELOPMENT THIS AFTERNOON WITHIN A MOIST
   AND MODERATELY UNSTABLE AIR MASS WITH MLCAPE OF 1000-2000 J/KG. 
   DEEP-LAYER FLOW FIELD WOULD SUPPORT THE SEWD MOTION OF TSTM CLUSTERS
   WITH A RISK FOR SOME HAIL AND DAMAGING WINDS SPREADING TOWARD THE
   CNTRL GULF COAST THROUGH THIS EVENING.
   
   ..MEAD/ROGERS.. 05/30/2012
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z