The SPC is forecasting ...Severe thunderstorms expected over parts of the Midwest and Ohio Valley later today and tonight....   Please read the latest public statement about this event.  View What is a Watch? clip.

   SPC AC 131243

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0743 AM CDT MON JUL 13 2015

   VALID 131300Z - 141200Z

   ...THERE IS A MDT RISK OF SVR TSTMS MAINLY THIS AFTERNOON THROUGH
   LATE EVENING FROM EXTREME ERN IA ACROSS CENTRAL IL TO SW INDIANA AND
   WRN KY...

   ...THERE IS AN ENH RISK OF SVR TSTMS TODAY INTO EARLY TONIGHT FROM
   ERN IA/IL TO SW OH...EXTREME WRN WV...ERN KY...AND NRN MIDDLE/ERN
   TN...

   ...THERE IS A SLGT RISK OF SVR TSTMS THROUGH EARLY TONIGHT
   SURROUNDING THE ENH RISK AREA...FROM THE UPPER MS VALLEY TO THE TN
   VALLEY...

   ...THERE IS A MRGL RISK OF SVR TSTMS THIS AFTERNOON ACROSS THE SE
   STATES...KS...AND CENTRAL MN...

   ...THERE IS A MRGL RISK OF SVR TSTMS ACROSS PARTS OF THE NRN ROCKIES
   THIS AFTERNOON...

   ...SUMMARY...
   MULTIPLE ROUNDS OF SEVERE THUNDERSTORMS CAPABLE OF DAMAGING
   WINDS...TORNADOES AND LARGE HAIL ARE LIKELY TODAY AND TONIGHT ACROSS
   MUCH OF THE MIDWEST...BUT ESPECIALLY ACROSS PORTIONS OF
   ILLINOIS...INDIANA...AND KENTUCKY.

   ...CORN BELT AND OH VALLEY REGION THROUGH TONIGHT...
   A SHORTWAVE TROUGH OVER THE NRN PLAINS/UPPER MS VALLEY...WITH
   SEVERAL EMBEDDED SPEED MAXIMA...WILL PROGRESS SEWD AROUND THE NE
   PERIPHERY OF A CLOSED UPPER HIGH OVER THE SRN PLAINS.  AN ONGOING
   MCS AND MCV NEAR CHICAGO AS OF 12Z WILL LIKELY CONTINUE TO MOVE SEWD
   TODAY IN ASSOCIATION WITH THE INTERACTION OF ITS COLD POOL AND A
   PRE-EXISTING FRONT FROM NE IL ACROSS WRN/SRN INDIANA TO NRN KY. 
   SURFACE HEATING/DESTABILIZATION IN ADVANCE OF THIS MCS SHOULD ALLOW
   THE CONVECTION TO MAINTAIN INTENSITY THROUGH LATE MORNING AND INTO
   THE AFTERNOON...WITH THE CONTINUED RISK FOR DAMAGING OUTFLOW GUSTS
   FROM NE IL/NW INDIANA THIS MORNING INTO KY BY EARLY-MID AFTERNOON. 
   THE INTENSITY OF THE DAMAGING GUST RISK IS IN QUESTION AS FAR E AND
   SE AS THE INDIANAPOLIS AND LOUISVILLE AREAS SINCE THE RELATIVELY
   EARLY ARRIVAL OF THE MCS /ROUGHLY 16Z AT IND AND 19Z AT LOU/ WILL BE
   SUBOPTIMAL WITH RESPECT TO DIURNAL DESTABILIZATION.

   OUTFLOW TRAILING WWD AND NWWD FROM THIS EARLY MCS WILL PROVIDE A
   FOCUS FOR ADDITIONAL SEVERE THUNDERSTORM DEVELOPMENT THIS
   AFTERNOON/EVENING ACROSS EXTREME ERN IA INTO IL.  STRONG TO EXTREME
   BUOYANCY /MLCAPE OF 4000-5500 J PER KG/ IS EXPECTED ALONG THIS
   BOUNDARY BY MID AFTERNOON AS SURFACE TEMPERATURES WARM TO NEAR 90 F
   WITH MID-UPPER 70S BOUNDARY LAYER DEWPOINTS...BENEATH THE ERN EXTENT
   OF AN ELEVATED MIXED LAYER PLUME.  LOW-LEVEL ASCENT ALONG THE
   REMNANT OUTFLOW SHOULD BE SUFFICIENT TO INITIATE ADDITIONAL STORMS
   BY MID-LATE AFTERNOON...WITH STORMS SUBSEQUENTLY SPREADING SEWD
   THROUGH THIS EVENING AND TONIGHT.

   THE ENVIRONMENTAL PARAMETER SPACE /LARGE CAPE AND EFFECTIVE BULK
   WIND DIFFERENCES AOA 50 KT/ FAVORS INTENSE SUPERCELLS WITH THE
   INITIAL STORM DEVELOPMENT THIS AFTERNOON ACROSS EXTREME ERN IA INTO
   NW AND CENTRAL IL.  SOME ENHANCEMENT TO LOW-LEVEL SHEAR ALONG THE
   OUTFLOW BOUNDARY...IN CONJUNCTION WITH THE EXTREME BUOYANCY AND RICH
   MOISTURE...WILL SUPPORT THE RISK FOR A STRONG TORNADO OR TWO AND
   VERY LARGE HAIL EARLY IN THE STORM EVOLUTION.  THE CONVECTION SHOULD
   GROW UPSCALE INTO ANOTHER MCS THIS EVENING WHILE SURGING SEWD/SSEWD
   ACROSS IL...WITH AN ACCOMPANYING RISK FOR SWATHS OF DAMAGING WINDS.

   ..THOMPSON/GLEASON.. 07/13/2015

   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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