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 282000
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0300 PM CDT SAT MAY 28 2011
   
   VALID 282000Z - 291200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF MN/WI...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF THE CENTRAL
   PLAINS TO MID MS AND LOWER OH VALLEYS...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS OVER NORTHEAST NY AND MUCH OF
   VT...
   
   ...UPPER MIDWEST...
   TSTMS WILL CONTINUE TO DEVELOP ALONG AND AHEAD OF A WIND SHIFT
   MOVING INTO THE UPPER MS VALLEY THIS FORECAST PERIOD.  STRONGER
   INSTABILITY HAS DEVELOPED FARTHER SWD INTO SRN MN.  THIS COMBINED
   WITH EFFECTIVE BULK SHEAR 40-50 KT WILL CONTINUE TO SUPPORT AN
   ORGANIZED STRONG TO SEVERE STORM THREAT INTO THE EVENING...AND THUS
   HAVE EXTENDED THE SLIGHT RISK SWD ACROSS MUCH OF SRN MN AND INTO
   WEST CENTRAL WI.
   
   ...MID MS AND LOWER OH VALLEYS...
   ONGOING STRONG TO SEVERE STORMS MOVING EWD AND SEWD ACROSS IL/IND
   ALONG ERN EXTENT OF STEEP MIDLEVEL LAPSE RATES PLUME WILL CONTINUE
   TO SUPPORT ADDITIONAL DEVELOPMENT AS A MIDLEVEL IMPULSE SHIFTS EWD. 
   GIVEN THE SEWD EXTENSION OF A WARM FRONT INTO SERN IL/WRN KY AND
   SOME TREND OF THE WRN MOST STORMS TO TURN SEWD...THIS OUTLOOK HAS
   EXTENDED THE SLIGHT RISK BOTH SEWD AND EWD INTO THE LOWER OH VALLEY.
   
   
   ...SERN KS/NORTH CENTRAL-NERN OK/SWRN MO...
   VISIBLE SATELLITE IMAGERY SHOWED A CU FIELD DEVELOPING OVER NORTH
   CENTRAL OK INTO SERN KS.  FURTHER VERTICAL DEVELOPMENT IS POSSIBLE
   AS A MIDLEVEL IMPULSE NOTED IN BACKING 700 MB WINDS OVER OK
   PROGRESSES ENEWD THIS FORECAST PERIOD.  STRONG CAP PER 17Z LAMONT OK
   SOUNDING SUGGESTS IT WILL BE DIFFICULT FOR STORMS TO FORM. 
   HOWEVER...IF ACTIVITY DOES DEVELOP AS INDICATED BY RECENT RUNS OF
   THE EXPERIMENTAL WRF-HRRR...THEN SEVERE STORMS WOULD BE LIKELY. 
   THUS...SLIGHT RISK AREA HAS BEEN EXTENDED SSWWD.
   
   ..PETERS.. 05/28/2011
   
   .PREV DISCUSSION... /ISSUED 1254 PM CDT SAT MAY 28 2011/
   
   AMENDED TO ADD SLIGHT RISK IN NY/NEW ENGLAND
   
   ...NY/NEW ENGLAND...
   WEAKENING CYCLONIC FLOW REMAINS ACROSS PORTIONS OF NY AND WESTERN
   NEW ENGLAND TODAY.  SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED
   TO FORM IN THIS AREA THIS AFTERNOON.  TEMPERATURES IN THE 70S AND
   DEWPOINTS IN THE MID 60S WILL YIELD SUFFICIENT CAPE FOR A RISK OF A
   FEW SEVERE CELLS CAPABLE OF HAIL AND DAMAGING WINDS.  PLEASE REFER
   TO MCD 1004 AND WW 391 FOR FURTHER DETAILS.
   
   ...MN/WI...
   A WEAKENING UPPER LOW IS CURRENTLY OVER ND/SRN MANITOBA.  A SERIES
   OF SHORTWAVE TROUGHS ARE ROTATING AROUND THE LOW...INCLUDING ONE
   OVER WESTERN ND/SD.  THIS FEATURE IS FORECAST TO MOVE EASTWARD AND
   AFFECT MN/WI LATER TODAY.  THUNDERSTORMS ARE EXPECTED TO FORM IN
   WESTERN MN BY MID AFTERNOON AND SPREAD EASTWARD TOWARD WESTERN LAKE
   SUPERIOR...NORTHERN WI...AND THE ARROWHEAD REGION THIS EVENING. 
   INSTABILITY IS ONLY MARGINAL FOR AN ORGANIZED SEVERE EVENT. 
   HOWEVER...STEEP MID LEVEL LAPSE RATES...COLD TEMPERATURES AND FAST
   FLOW ALOFT WILL SUPPORT A RISK OF A FEW FAST-MOVING CLUSTERS OF
   THUNDERSTORMS CAPABLE OF HAIL AND LOCALLY DAMAGING WINDS.  STORMS
   SHOULD DIMINISH A FEW HOURS AFTER SUNSET.
   
   ...CENTRAL PLAINS INTO MID MS VALLEY...
   CONVECTIVE EVOLUTION IS UNCERTAIN ACROSS THIS AREA TODAY.  WEAK MID
   LEVEL HEIGHT RISES AND WEAK FORCING MECHANISMS SUGGEST CONVECTIVE
   COVERAGE WILL BE QUITE LIMITED THROUGH MOST OF THE FORECAST PERIOD. 
   THROUGH THE AFTERNOON AND EARLY EVENING...MOST LIKELY AREA FOR
   ISOLATED SEVERE STORMS WOULD BE FROM EASTERN KS INTO PORTIONS OF
   MO/IL WHERE STRONG HEATING AND RESIDUAL BOUNDARIES FROM MORNING
   CONVECTION MIGHT AID DEVELOPMENT.  IF STORMS CAN FORM...STRONG
   INSTABILITY AND SUFFICIENT EFFECTIVE SHEAR WOULD SUPPORT A RISK OR
   ORGANIZED OR EVEN SUPERCELL STORMS CAPABLE OF LARGE HAIL AND
   DAMAGING WINDS.
   
   OVERNIGHT...STRENGTHENING SOUTHERLY LOW LEVEL WINDS WILL ENHANCE
   WARM ADVECTION AND POSSIBLY LEAD TO MORE WIDESPREAD THUNDERSTORMS
   ALONG THE SLIGHT RISK AXIS.  LARGE HAIL WOULD BE THE MAIN THREAT
   WITH THESE STORMS FROM KS INTO IND.
   
   ...SC/GA/FL...
   STRONG DAYTIME HEATING IS OCCURRING FROM SC INTO THE FL
   PENINSULA...WHERE AFTERNOON MLCAPE VALUES WILL EXCEED 3000 J/KG. 
   WIND FIELDS ARE RELATIVELY WEAK...BUT COMBINATION OF COOL
   TEMPERATURES ALOFT AND MOIST THERMODYNAMIC PROFILE MAY BE SUFFICIENT
   FOR A FEW WET-MICROBURSTS IN STRONGER CELLS.
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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