May 24, 2010 1630 UTC Day 1 Convective Outlook
Updated: Mon May 24 16:12:24 UTC 2010
Probabilistic to Categorical Outlook Conversion Table
Public Severe Weather Outlook

The SPC is forecasting ...severe thunderstorms expected over parts of the central and northern high plains today and tonight....   Please read the latest public statement about this event.

Categorical Graphic
20100524 1630 UTC Day 1 Outlook Graphic
Probabilistic Tornado Graphic
20100524 1630 UTC Day 1 Tornado Probabilities Graphic
Torndao Legend Image
Probabilistic Damaging Wind Graphic
20100524 1630 UTC Day 1 Damaging Wind Probabilities Graphic
Wind Legend Image
Probabilistic Large Hail Graphic
20100524 1630 UTC Day 1 Large Hail Probabilities Graphic
Hail Legend Image
   SPC AC 241609
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1109 AM CDT MON MAY 24 2010
   
   VALID 241630Z - 251200Z
   
   ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON/EVENING FOR NW
   NEB...WRN SD...S CENTRAL ND...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT
   RISK...ACROSS MUCH OF THE GREAT PLAINS...
   
   ...CENTRAL/NRN PLAINS THROUGH EARLY TONIGHT...
   A STRONG NEGATIVE TILT MIDLEVEL TROUGH WILL EJECT NNEWD FROM THE
   CENTRAL ROCKIES TO THE NRN HIGH PLAINS AS AN ASSOCIATED SURFACE
   CYCLONE DEVELOPS NWD FROM CO TO THE WRN DAKOTAS ALONG A PRE-EXISTING
   BAROCLINIC ZONE.  IN ADVANCE OF THE CYCLONE...THE WARM FRONT WILL
   MOVE NWD FROM CENTRAL SD/MN THIS MORNING TO CENTRAL ND AND NW MN BY
   LATE AFTERNOON.  S OF THE WARM FRONT...A BROAD WARM SECTOR EXISTS
   WITH BOUNDARY LAYER DEWPOINTS OF 65-70 F BENEATH STEEP MIDLEVEL
   LAPSE RATES FROM THE UPPER MS VALLEY TO THE CENTRAL/SRN PLAINS. 
   DAYTIME HEATING WILL FURTHER INCREASE INSTABILITY AND WEAKEN
   CONVECTIVE INHIBITION...RESULTING IN A BROAD AREA OF MODERATE-STRONG
   INSTABILITY.
   
   THE SITUATION IS COMPLICATED SOMEWHAT BY A LEAD SHORTWAVE TROUGH NOW
   MOVING NNEWD OVER WRN OK/WRN KS.  SATELLITE IMAGERY SHOWS A LOOSE
   BAND OF LOW-MIDLEVEL CONVECTION PRECEDING THIS WAVE...AND A
   CONSENSUS OF MODEL FORECASTS SUGGESTS THAT PRE-FRONTAL CONVECTION
   WILL DEVELOP BY MIDDAY-EARLY AFTERNOON FROM OK NWD TO SD /ALREADY
   FORMING IN CENTRAL NEB/.  THESE STORMS WILL BE CAPABLE OF PRODUCING
   LARGE HAIL AND DAMAGING WINDS...WITH A GREATER RISK FOR SUPERCELLS
   FARTHER N INTO ERN SD AND SE ND LATER THIS AFTERNOON WHERE
   DEEP-LAYER AND LOW-LEVEL SHEAR WILL BE STRONGER IN PROXIMITY TO THE
   WARM FRONT.
   
   FARTHER W...INITIAL THUNDERSTORM DEVELOPMENT IS ALREADY OCCURRING
   ACROSS ERN CO...AND ADDITIONAL THUNDERSTORM DEVELOPMENT IS EXPECTED
   FROM NEAR THE SURFACE LOW SWD ALONG THE TRAILING SURFACE TROUGH/COLD
   FRONT BY EARLY-MID AFTERNOON.  HODOGRAPH CURVATURE AND FLOW
   ORIENTATION WILL BE MORE FAVORABLE FOR DISCRETE SUPERCELLS WITH
   TORNADOES CLOSER TO THE SURFACE LOW AND WARM FRONT IN SD.  CELL
   INTERACTIONS AND BACKED FLOW ALOFT SUGGEST THE POTENTIAL FOR UPSCALE
   GROWTH INTO LINE SEGMENTS ACROSS KS/NEB THIS EVENING...THOUGH
   DISCRETE SUPERCELLS WILL BE POSSIBLE FOR THE FIRST FEW HOURS
   AFTERNOON INITIATION.  FARTHER S...MORE ISOLATED SEVERE STORMS WILL
   ALSO BE POSSIBLE INTO THE TX PANHANDLE...INCLUDING THE POSSIBILITY
   OF SUPERCELLS ON THE SRN FRINGE OF THE STRONGER VERTICAL SHEAR.  THE
   SEVERE STORM THREAT IS EXPECTED TO DIMINISH EARLY TONIGHT AS THE
   SURFACE LOW OCCLUDES INVOF WRN ND AND FORCING FOR ASCENT WEAKENS
   WITHIN THE REMAINING STRONGLY SHEARED WARM SECTOR ACROSS THE ERN
   DAKOTAS/WRN MN.  
   
   ...MS VALLEY REGION THIS AFTERNOON...
   A WEAK MIDLEVEL VORTICITY LOBE IS ROTATING SWWD OVER SRN IL/WRN
   KY/WRN TN AROUND THE WRN PERIPHERY OF THE CLOSED LOW OVER SC.  THE
   PRESENCE OF THIS WAVE AND STRONG INSTABILITY UPSTREAM IN THE LOW
   LEVELS SUGGESTS THAT THE ISOLATED ONGOING STORM CLUSTERS FROM SRN IL
   TO WRN TN WILL LIKELY INCREASE IN COVERAGE/INTENSITY THIS AFTERNOON.
   VERTICAL SHEAR WILL REMAIN WEAK...BUT A STEEP LAPSE RATE ENVIRONMENT
   WILL SUPPORT A RISK FOR ISOLATED STRONG/DAMAGING DOWNBURSTS AND
   MARGINALLY SEVERE HAIL THIS AFTERNOON.
   
   ..THOMPSON/HURLBUT.. 05/24/2010
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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