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 081616
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1116 AM CDT SUN JUL 08 2012
   
   VALID 081630Z - 091200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MIDDLE MS VALLEY EWD
   TO THE DELMARVA REGION...
   
   ...CENTRAL VA INTO THE DELMARVA REGION...
   A LONG WAVE TROUGH IS FORECAST TO REMAIN OVER THE NERN STATES AS A
   SERIES OF VORTICITY MAX/SHORT WAVE TROUGHS MOVE SEWD/EWD ACROSS SRN
   ONTARIO AND QUEBEC.  THE SRN EDGE OF STRONGER NWLY FLOW ALOFT IS
   EXPECTED TO TRANSLATE SLOWLY SWD ACROSS THE MID ATLANTIC REGION AS
   THE LONG WAVE TROUGH GRADUALLY DEEPENS...AS AN ASSOCIATED SURFACE
   COLD FRONT SAGS SWD ACROSS THE REGION.  VERY WARM/MOIST CONDITIONS
   PERSIST FROM NEAR THE COLD FRONT SWD INTO THE WARM SECTOR.  WITH
   MINIMAL CLOUDS OVER THE REGION STRONG DIABATIC HEATING IN THE
   PRE-CONVECTIVE ENVIRONMENT WILL CONTINUE THIS AFTERNOON WITH SURFACE
   TEMPERATURES REACHING THE 100-105 RANGE.  12Z IAD RAOB INDICATES
   STEEP LAPSE RATES BELOW ~600 MB...AND WHEN COUPLED WITH AMPLE LOW
   LEVEL MOISTURE MLCAPE WILL REACH 3500-4000 J/KG.
   
   THUNDERSTORMS ARE EXPECTED TO DEVELOP BY EARLY/MID AFTERNOON OVER
   PARTS OF NRN VA AND MD WITH POTENTIALLY RAPID INTENSIFICATION AS
   THEY SPREAD/DEVELOP EWD AND SEWD INTO THE EVENING HOURS.  MID LEVEL
   WIND SPEEDS OF 20-30 KT AND RESULTANT DEEP LAYER SHEAR WILL PROMOTE
   A FEW ORGANIZED MULTICELL CLUSTERS/SHORT LINE SEGMENTS CAPABLE OF
   PRODUCING DAMAGING WIND GUSTS /ENHANCED BY DCAPE OF 1000-1500 J PER
   KG/ AND OCCASIONAL LARGE HAIL. 
   
   ...APPALACHIANS WWD ACROSS PARTS OF THE OH AND MIDDLE MS VALLEYS...
   THE AFOREMENTIONED COLD FRONT EXTENDS WWD ACROSS SRN PARTS OF
   INDIANA AND IL INTO CENTRAL MO...AND IS EXPECTED TO SAG SLOWLY SWD
   INTO TONIGHT.  STRONG DIABATIC HEATING ALONG THE FRONTAL ZONE WITHIN
   A VERY MOIST AND UNSTABLE ENVIRONMENT /MLCAPE OF 2500-3500 J/KG
   EXPECTED THIS AFTERNOON/ WILL WEAKEN THE CAP SUFFICIENTLY FOR
   THUNDERSTORMS TO INCREASE THIS AFTERNOON.  WATER VAPOR IMAGERY SHOWS
   CYCLONIC PERTURBATION ALONG THE MOISTURE DISCONTINUITY OVER THE
   MID-SOUTH REGION AND AS THIS FEATURE MOVES NWWD THIS AFTERNOON...IT
   MAY ENHANCE CONVECTIVE DEVELOPMENT OVER THE LOWER OH/MIDDLE MS
   VALLEY AREA.  ALTHOUGH WINDS ALOFT AND VERTICAL SHEAR ARE EXPECTED
   TO REMAIN WEAK FAVORING PRIMARILY PULSE STORMS...POTENTIAL EXISTS
   FOR SEVERAL MORE PERSISTENT CLUSTERS TO DEVELOP IF CONVECTIVE
   OUTFLOWS ARE ABLE TO BECOME ORGANIZED ON THE MESOSCALE.
   
   ...CENTRAL AND ERN PARTS OF OREGON/WA...
   WATER VAPOR IMAGERY SHOWS INCREASING MID LEVEL MOISTURE OVER OREGON
   IN ADVANCE OF A WEAK VORTICITY MAX CURRENTLY OFF THE NRN CA COAST. 
   AS THE VORTICITY MAX LIFTS NNEWD...SLY MID/UPPER LEVEL WINDS ARE
   FORECAST TO STRENGTHEN WITH A RESULTANT INCREASE IN DEEP LAYER SHEAR
   OVER THE AREA.  STRONG AFTERNOON HEATING AND SUFFICIENT MOISTURE
   AIDED BY OROGRAPHIC FORCING FOR ASCENT IS EXPECTED TO RESULT IN
   HIGH-BASED THUNDERSTORM DEVELOPMENT BY MID/LATE AFTERNOON...WITH
   ACTIVITY SPREADING NWD FROM OREGON INTO WA THROUGH THE EVENING.
   STRONGER STORMS WILL BE CAPABLE OF PRODUCING STRONG WIND GUSTS AND
   ISOLATED HAIL.
   
   ..WEISS/GARNER.. 07/08/2012
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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