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 231953
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0253 PM CDT FRI MAR 23 2012
   
   VALID 232000Z - 241200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF IL...IND...KY
   AND MIDDLE TN...
   
   SEVERAL CHANGES HAVE BEEN MADE TO THE OUTLOOK AT 20Z. THE FIRST
   CHANGE IS TO TRIM THE WRN EDGE OF THE SLIGHT RISK AREA. THIS REMOVES
   PARTS OF ERN MO...SW IL...FAR WRN KY...MIDDLE TN AND NRN AL WHERE
   DRY AIR IS INTRUDING FROM THE SOUTHWEST. DUE TO THE DRIER AIR...HAVE
   ALSO TRIMMED THE WRN EDGE OF THUNDER FROM ACROSS THE MID-MS VALLEY
   AND CNTRL GULF COAST STATES. A SECOND CHANGE IS TO NARROW THE 5
   PERCENT TORNADO PROBABILITY ACROSS ECNTRL IL TO CORRESPOND BETTER
   WITH THE ONGOING TORNADIC ACTIVITY. A THIRD CHANGE TO THE OUTLOOK IS
   TO NARROW AND EXTEND THE 5 PERCENT WIND DAMAGE AND 2 PERCENT TORNADO
   PROBABILITIES SLIGHTLY EWD INTO SW-SCNTRL GA TO ACCOUNT FOR A LINE
   OF THUNDERSTORMS ONGOING IN SE AL AND THE WRN FL PANHANDLE.
   
   ..BROYLES.. 03/23/2012
   
   .PREV DISCUSSION... /ISSUED 1125 AM CDT FRI MAR 23 2012/
   
   ...MID MS/LOWER OH VALLEY INTO TN VALLEY...
   UPPER LOW OVER SWRN MO IS FORECAST TO MOVE EWD TODAY AS STRONGEST
   WINDS ALOFT TRANSLATE ACROSS SRN PERIPHERY OF THE CLOSED
   CIRCULATION...WITH THE SYSTEM REACHING ERN MO THIS EVENING AND THE
   LOWER OH VALLEY BY THE END OF THE PERIOD.  OCCLUDED SURFACE LOW WILL
   CONTINUE EWD BENEATH THE UPPER SYSTEM...WITH THE PRIMARY LOWER LEVEL
   MOISTURE AXIS LOCATED AHEAD OF THE LOW WITH SURFACE DEW POINTS IN
   THE 60S EXTENDING FROM THE CENTRAL GULF COAST NWD ACROSS THE TN AND
   OH VALLEYS.  COLD MID LEVEL TEMPERATURES REMAIN ASSOCIATED WITH THE
   UPPER LOW /-26C AT 500 MB/...RESULTING IN STEEPER LAPSE RATES FROM
   MO EWD INTO THE MID MS AND LOWER OH VALLEYS.  ALTHOUGH LOW LEVEL
   MOISTURE IS MARGINAL CLOSER TO THE LOW CENTER WITH DEW POINTS IN THE
   40S-LOWER 50S OVER MO AND WRN IL...UNSTABLE CONDITIONS WILL PERSIST
   ACROSS THIS AREA UNTIL THE UPPER LOW PROGRESSES EWD.
   
   SATELLITE IMAGERY SUGGESTS DYNAMIC FORCING FOR LARGE SCALE ASCENT IS
   ENHANCED OVER PARTS OF THE MID MS VALLEY WITHIN THE LEFT EXIT REGION
   OF A CYCLONIC UPPER JET ACROSS NRN AR...AND THIS WILL SPREAD
   EWD/NEWD THIS AFTERNOON AND EVENING IN ADVANCE OF THE UPPER LOW. 
   SEVERAL SHORT NORTH/SOUTH LINES OF STORMS HAVE DEVELOPED THIS
   MORNING OVER SERN MO AND WRN KY INTO SRN IL IN ASSOCIATION WITH THE
   JET DYNAMICS...AND STORMS IN THIS AREA MAY INCREASE IN INTENSITY
   INTO THIS AFTERNOON AS THEY SPREAD/DEVELOP NEWD ACROSS THE MID MS
   VALLEY AND LOWER OH VALLEY AREA.  VISIBLE SATELLITE IMAGERY SHOWS
   SUBSTANTIAL BREAKS IN THE CLOUD COVER FROM SERN MO/WRN PARTS OF TN
   AND KY INTO IL INDICATING CORRIDORS OF ENHANCED HEATING WILL OCCUR
   INTO THIS AFTERNOON.  INCREASING ZONES OF INSTABILITY WITH MLCAPE OF
   500-1000 J/KG THIS AFTERNOON WITHIN A KINEMATIC ENVIRONMENT
   CHARACTERIZED BY DEEP LAYER SHEAR OF 35-50 KT IN THE LOWEST 6 KM
   WILL SUPPORT ORGANIZED SEVERE STORMS CAPABLE OF PRODUCING  LARGE
   HAIL AND DAMAGING WINDS.  ISOLATED TORNADOES MAY ALSO BE
   POSSIBLE...ESPECIALLY FROM PARTS OF CENTRAL IL INTO SWRN INDIANA.
   
   FARTHER SOUTH...STORMS MAY DEVELOP ALONG THE ADVANCING COLD FRONT
   INTO PARTS OF THE TN VALLEY LATER THIS AFTERNOON AND EVENING AS THE
   AIR MASS DESTABILIZES WITHIN THE CURRENT CLOUD-FREE REGION AHEAD OF
   THE FRONT.  FAVORABLE VERTICAL SHEAR /50 KT IN LOWEST 6 KM/ AND
   MLCAPE NEAR 1000 J/KG WILL SUPPORT SEVERE STORM POTENTIAL DURING THE
   MID/LATE AFTERNOON THROUGH THE EVENING HOURS.
   
   ...SRN AL/NWRN FL...
   A BAND OF STORMS CONTINUES FROM SOUTH OF MOB ENEWD INTO SERN
   AL...ALONG THE SERN EDGE OF STRONGER WSWLY WINDS ALOFT.  MOIST LOW
   LEVEL PROFILES AND VEERING WINDS WITH HEIGHT ARE SUPPORTING A FEW
   ORGANIZED CONVECTIVE STRUCTURES INCLUDING SEVERAL SUPERCELLS BASED
   ON LATEST RADAR.  CONVECTION WILL PERSIST THROUGH THE AFTERNOON
   HOWEVER OVERALL SEVERE THREAT IS EXPECTED TO SLOWLY DIMINISH AS LOW
   LEVEL WINDS GRADUALLY VEER TO A MORE WESTERLY DIRECTION AND DECREASE
   IN SPEED.
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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