The SPC is forecasting ...severe thunderstorms expected over parts of the central and southern plains this afternoon through tonight....   Please read the latest public statement about this event.  View What is a Watch? clip.

   SPC AC 291228

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0728 AM CDT WED MAY 29 2013

   VALID 291300Z - 301200Z

   ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF THE ERN TX
   PANHANDLE...NW TX...WRN TO CNTRL OK AND WRN TO CNTRL KS...

   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE GREAT
   PLAINS...MID-MO VALLEY AND MID TO UPPER MS VALLEY...

   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE ERN GREAT
   LAKES REGION...NRN APPALACHIAN MTNS AND WRN TO SRN NEW ENGLAND...

   ...WIDESPREAD SEVERE WEATHER WITH TORNADOES LIKELY THIS AFTERNOON
   AND EVENING ACROSS PARTS OF THE SRN AND CNTRL PLAINS

   ...SRN AND CNTRL PLAINS...
   A NEGATIVELY-TILTED UPPER-LEVEL TROUGH EXTENDING FROM THE FOUR
   CORNERS SWD INTO NRN MEXICO WILL MOVE EWD INTO THE CNTRL AND SRN
   HIGH PLAINS TODAY. AT THE SFC...A LOW WILL GRADUALLY DEEPEN ACROSS
   THE CNTRL HIGH PLAINS AS A DRYLINE SHARPENS THIS AFTERNOON. TO THE
   EAST OF THE DRYLINE ACROSS THE ERN TX PANHANDLE...WRN OK AND
   SOUTHWEST KS...SFC DEWPOINTS SHOULD BE IN THE 65 TO 70 F RANGE
   ALLOWING FOR STRONG DESTABILIZATION BY MIDDAY. THUNDERSTORMS SHOULD
   INITIATE ALONG AND EAST OF THE DRYLINE THIS AFTERNOON BUT THE TIMING
   OF INITIATION IS STILL UNCERTAIN. THE DETERMINISTIC MODELS SUGGEST
   THAT STORMS WILL INITIATE ALONG THE DRYLINE BY 18Z BUT THIS APPEARS
   TO BE TOO EARLY. THE CURRENT THINKING IS THAT CELL INITIATION WILL
   BE DELAYED UNTIL ABOUT 20Z...MORE IN LINE WITH SOME OF THE HI-RES
   GUIDANCE.  AS CELLS INITIATE...THE STRONG INSTABILITY SHOULD ENABLE
   RAPID CELL INTENSIFICATION. DUE TO THE AMOUNT OF INSTABILITY...STEEP
   MID-LEVEL LAPSE RATES AND MODERATE DEEP LAYER SHEAR...A SEVERE
   THREAT SHOULD DEVELOP ACROSS A WIDESPREAD AREA LATE THIS AFTERNOON
   INTO THE EVENING. THE MAGNITUDE OF INSTABILITY AND DEEP LAYER SHEAR
   COMBINED WITH STEEP LAPSE RATES AND STRONG LOW-LEVEL SHEAR WILL MAKE
   A SIGNIFICANT SEVERE EVENT POSSIBLE ACROSS THE MODERATE RISK AREA.

   FORECAST SOUNDINGS AT 21Z FROM DODGE CITY...CHILDRESS AND LAWTON
   SHOW LOADED-GUN SOUNDINGS WITH MLCAPE OF 2000 TO 3500 J/KG...0-6 KM
   SHEAR AROUND 40 KT AND 700 TO 500 MB LAPSE RATES OF 8.0 C/KM. THIS
   IMPRESSIVE ENVIRONMENT SHOULD EASILY SUPPORT SUPERCELL DEVELOPMENT
   AND LARGE HAIL WILL BE LIKELY WITH ANY ROBUST UPDRAFT THAT
   INITIATES. HAILSTONES GREATER THAN 2 INCHES IN DIAMETER WILL BE
   POSSIBLE WITH SUPERCELLS THAT BECOME DOMINANT. TORNADOES WILL ALSO
   BE POSSIBLE WITH THE MORE ORGANIZED SUPERCELLS WITH THE THREAT
   INCREASING LATE THIS AFTERNOON AS STORMS MOVE EWD AWAY FROM THE
   DRYLINE. THE GREATEST POTENTIAL FOR STRONG TORNADOES THIS AFTERNOON
   IS EXPECTED TO DEVELOP FROM NEAR DODGE CITY SWD ACROSS THE ERN TX
   PANHANDLE AND WRN OK TO AROUND CHILDRESS WHERE SFC WINDS ARE LOCALLY
   BACKED. DUE TO IMPRESSIVE SHEAR AND THERMODYNAMICS...A 15 PERCENT
   TORNADO CONTOUR HAS BEEN ADDED FROM SW KS SWD INTO NW TX WHERE
   LOW-LEVEL SHEAR SHOULD BE ENHANCED BY A STRENGTHENING 40 TO 55 KT
   LOW-LEVEL JET EARLY THIS EVENING. SWATHS OF WIND DAMAGE WILL BE
   POSSIBLE WITH THE MORE INTENSE SUPERCELLS AND BOW ECHOS.

   A SEVERE THREAT SHOULD ALSO DEVELOP FROM WRN AND CNTRL NEB SEWD INTO
   NE KS THIS AFTERNOON AND EVENING. HOWEVER...SFC DEWPOINTS SHOULD BE
   LOWER THAN IN AREAS TO THE SOUTH AND THIS COULD KEEP SEVERE THREAT
   COVERAGE SLIGHTLY LESS WIDESPREAD. LARGE HAIL...WIND DAMAGE AND A
   FEW TORNADOES WILL BE POSSIBLE ACROSS NRN PARTS OF THE CNTRL PLAINS.


   ...NRN PLAINS/UPPER MS VALLEY...
   SOUTH TO SOUTHWEST FLOW WILL BE IN PLACE ACROSS THE NRN PLAINS AND
   UPPER MS VALLEY TODAY AS A NEGATIVELY-TILTED UPPER-LEVEL TROUGH
   MOVES EWD INTO THE CNTRL HIGH PLAINS. MODEL FORECASTS DEVELOP AN
   AXIS OF MODERATE INSTABILITY FROM NE NEB EXTENDING NWD ACROSS ECNTRL
   SD INTO SE ND WHERE SFC DEWPOINTS SHOULD BE IN THE 55 TO 60 F RANGE.
   A CAPPING INVERSION SHOULD WEAKEN QUICKLY BY MIDDAY ALLOWING FOR
   SCATTERED CONVECTIVE INITIATION ALONG AND SOUTH OF A WARM FRONT FROM
   ERN SD EWD ACROSS SRN MN INTO SCNTRL WI. THUNDERSTORMS SHOULD ALSO
   INITIATE FURTHER WEST NEAR THE NOSE OF THE LOW-LEVEL JET AND IN WRN
   NEB AND WRN SD ALONG THE WRN EDGE OF MODERATE INSTABILITY. DUE TO
   THE MODERATELY UNSTABLE AIRMASS ACROSS MUCH OF THE NRN PLAINS AND
   UPPER MS VALLEY...A SEVERE THREAT IS FORECAST FOR A BROAD AREA.

   FORECAST SOUNDINGS AT NORFOLK NEB...ABERDEEN SD AND SOUTH OF
   LACROSSE WI GENERALLY SHOW SBCAPE VALUES REACHING THE 1500 TO 2500
   J/KG RANGE BY LATE THIS AFTERNOON. THIS COMBINED WITH 35 TO 45 KT OF
   DEEP LAYER SHEAR SHOULD BE FAVORABLE FOR SEVERE THUNDERSTORM
   DEVELOPMENT WITH SUPERCELLS POSSIBLE ESPECIALLY WHERE
   DESTABILIZATION MAXIMIZES. SUPERCELLS SHOULD HAVE A THREAT FOR LARGE
   HAIL WITH THE GREATEST POTENTIAL OVER SRN SECTIONS OF THE NRN PLAINS
   WHERE MID-LEVEL LAPSE RATES ARE FORECAST TO BE STEEP AND TEMPS ALOFT
   WILL BE COLD ASSOCIATED WITH THE APPROACHING UPPER-LEVEL TROUGH. A
   WIND DAMAGE THREAT WILL ALSO BE LIKELY WITH ANY ORGANIZED
   LINE-SEGMENT THAT CAN PERSIST INTO THE EARLY EVENING WHEN THE
   LOW-LEVEL JET IS FORECAST TO MARKEDLY STRENGTHEN. INCREASING
   LOW-LEVEL SHEAR DURING THE EARLY EVENING WILL ALSO MAKE TORNADOES
   POSSIBLE WITH SUPERCELLS AND BOWING LINE-SEGMENTS.

   ...GREAT LAKES...
   SOUTH TO SOUTHWEST FLOW WILL BE IN PLACE ACROSS THE LOWER OH VALLEY
   WITH AN UPPER-LEVEL RIDGE LOCATED IN THE GREAT LAKES REGION. AT THE
   SFC...SOUTH TO SWLY FLOW WILL EXIST FROM THE OH VALLEY NWD INTO
   LOWER MI WHERE SFC DEWPOINTS SHOULD BE IN THE LOWER TO MID 60S F
   ALLOWING FOR MODERATE DESTABILIZATION BY THIS AFTERNOON. IN SPITE OF
   LIMITED LARGE-SCALE ASCENT...THUNDERSTORM DEVELOPMENT MAY OCCUR LATE
   THIS MORNING OR EARLY THIS AFTERNOON WHERE GAPS IN THE CLOUD COVER
   ALLOW FOR STRONGER SFC HEATING. THE MODELS SUGGEST THAT THE GREATEST
   POTENTIAL FOR THUNDERSTORM DEVELOPMENT WILL EXIST FROM NRN IL EWD
   ACROSS NRN IND...NRN OH AND SRN LOWER MI. A MARGINAL WIND DAMAGE
   THREAT WILL BE POSSIBLE WITH STORMS THAT CAN DEVELOP IN AREAS THAT
   DESTABILIZE THE MOST AND WHERE LOW-LEVEL LAPSE RATES BECOME
   STEEPEST.

   ...LOWER GREAT LAKES/NEW ENGLAND...
   AN UPPER-LEVEL TROUGH WILL MOVE EWD ACROSS THE LOWER GREAT LAKES
   REGION INTO NEW ENGLAND TODAY. AT THE SFC...A MOIST AXIS SHOULD BE
   IN PLACE FROM THE MID-ATLANTIC EXTENDING NNWWD INTO CNTRL NY ALONG
   WHICH MODERATE INSTABILITY MAY DEVELOP BY AFTERNOON.  MODEL
   FORECASTS SUGGEST STORMS WILL INITIATE ALONG THE INSTABILITY
   GRADIENT FROM LAKE ERIE ENEWD INTO UPSTATE NEW YORK NEAR THE AXIS OF
   A 30 TO 40 KT LOW-LEVEL JET. AS THUNDERSTORMS EXPAND IN COVERAGE AND
   MOVE ESEWD INTO NE PA...THE HUDSON RIVER VALLEY AND WRN NEW ENGLAND
   A SEVERE THREAT WILL BE POSSIBLE DURING THE MID TO LATE AFTERNOON.

   FORECAST SOUNDINGS LATE THIS AFTERNOON AT ALBANY NY...SCRANTON PA
   AND SPRINGFIELD MA GENERALLY SHOW MLCAPE VALUES IN THE 1000 TO 1500
   J/KG RANGE WITH 30 TO 40 KT OF DEEP LAYER SHEAR. THIS COMBINED WITH
   STEEP LOW-LEVEL LAPSE RATES AND UNIDIRECTIONAL WIND PROFILES ABOVE
   THE BOUNDARY LAYER SHOULD BE FAVORABLE FOR SEVERE MULTICELL
   LINE-SEGMENTS WITH WIND DAMAGE POTENTIAL. A SUPERCELL THREAT WILL
   ALSO BE POSSIBLE WHERE THE STRONGEST SFC HEATING OCCURS. IF
   SUPERCELLS CAN DEVELOP...THEN AN ISOLATED THREAT FOR TORNADOES AND
   HAIL WILL BE POSSIBLE LATE THIS AFTERNOON.

   ..BROYLES/BOTHWELL.. 05/29/2013

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