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 120542
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1242 AM CDT TUE JUL 12 2011
   
   VALID 121200Z - 131200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS OVER MUCH OF WRN AND CNTRL
   MT...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CNTRL HIGH PLAINS EWD
   ACROSS THE OH AND TN VALLEY AND INTO THE MID ATLANTIC...
   
   ...SYNOPSIS...
   AN UPPER HIGH WILL REMAIN CENTERED OVER THE SRN PLAINS...WITH RIDGE
   AXIS EXTENDING NWD INTO THE NRN HIGH PLAINS AT 00Z. THE AXIS OF
   CONTRACTION WILL STRETCH FROM NERN CO INTO THE OH VALLEY...WITH
   UPPER 60S TO LOWER 70S F DEWPOINTS ALONG IT AND STRONG INSTABILITY.
   
   STRONG WLY FLOW ASSOCIATED WITH A POSITIVELY TILTED UPPER TROUGH
   WILL STRETCH FROM THE GREAT LAKES INTO NEW ENGLAND. A SURFACE TROUGH
   WILL EXTEND SWD FROM A LOW OVER NEW BRUNSWICK SWD INTO THE MID
   ATLANTIC DURING THE DAYTIME...WHERE NWLY FLOW WILL EXIST ALOFT ON
   THE ERN EDGE OF THE PLAINS RIDGE.
   
   TO THE W...AN UPPER LOW WILL DROP SWD ACROSS THE PACIFIC NW
   PROVIDING SLY FLOW ACROSS ID AND INTO WRN MT WHILE A WEAK SURFACE
   TROUGH DEEPENS FROM ERN ORE INTO WRN MT.
   
   ...SERN VA INTO ERN NC...
   A VERY MOIST AND UNSTABLE AIR MASS WILL DEVELOP DURING THE DAY FROM
   SERN VA INTO THE CNTRL AND ERN CAROLINAS WITH LOW TO MID 70S F
   DEWPOINTS AND STRONG HEATING. LOW LEVEL LAPSE RATES WILL BE
   SUFFICIENTLY STEEP TO ERODE CIN...WITH MUCAPE IN EXCESS OF 2000
   J/KG. A WEAK LEE TROUGH WILL HELP LOW LEVEL CONVERGENCE...AND 850 MB
   FLOW WILL BE CONFLUENT FROM VA INTO NC ON THE SRN FRINGE OF THE NERN
   TROUGH. THUS...SCATTERED SEVERE THUNDERSTORMS ARE EXPECTED TO
   DEVELOP BY LATE AFTERNOON...POSSIBLY MERGING INTO AN MCS WITH A
   THREAT OF DAMAGING DOWNBURSTS AND MARGINALLY SEVERE HAIL.
   
   ...CNTRL HIGH PLAINS INTO SRN NEB/NRN KS...
   DAYTIME HEATING AND ELY UPSLOPE FLOW WILL ONCE AGAIN LEAD TO
   AFTERNOON STORM DEVELOPMENT FROM ERN WY INTO NERN CO. CIN MAY BE
   SUBSTANTIAL FARTHER E INTO WRN NEB IN PART DUE TO EXPECTED MORNING
   RAIN/STORMS...BUT HEATING OVER THE SRN PLAINS ALONG WITH POSSIBLE
   OUTFLOW BOUNDARIES OVER NEB AND KS MAY HELP TO FOCUS AFTERNOON
   DEVELOPMENT WITH MAINLY A WIND THREAT.
   
   ...MUCH OF WRN AND CNTRL MT...
   MLCAPE ON THE ORDER OF 1000 J/KG IS FORECAST OVER MUCH OF MT WHERE
   SELY SURFACE WINDS WILL MAINTAIN 50S F DEWPOINTS. MODEST DEEP LAYER
   SHEAR WILL EXIST DESPITE THE MAIN UPPER TROUGH BEING FARTHER W.
   STILL...UPSLOPE FLOW AND HEATING WILL LEAD TO STORMS DEVELOPING
   ACROSS ERN ID/WRN WY AND INTO SWRN MT...SPREADING NNEWD ACROSS MT.
   ALTHOUGH LOW LEVEL WINDS ARE WEAK...STEEP LAPSE RATES WILL FAVOR
   HAIL AND ALSO GUSTY AND LOCALLY SEVERE OUTFLOW WINDS.
   
   ...MID MO VALLEY EWD INTO THE TN VALLEY...
   RAIN AND STORMS ARE LIKELY TO BE ONGOING OVER PORTIONS OF NEB AND
   IA...ALONG A WEAK SURFACE BOUNDARY. A STRONGLY UNSTABLE AIR MASS
   WILL EXIST S OF THE OUTFLOW...WITH STORM REGENERATION POSSIBLE NEAR
   OLD BOUNDARIES. ALSO...ADDITIONAL PULSE STORMS MAY DEVELOP FARTHER
   SE ACROSS THE OH AND TN VALLEYS DUE TO HEATING AND SUBSTANTIAL
   PRECIPITABLE WATER CONTENT.
   
   ...MAINE...
   STRONG WIND SHEAR WILL EXIST TODAY WITH BROADLY CYCLONIC FLOW ALOFT.
   HOWEVER...FORECAST SOUNDINGS SHOW RELATIVELY POOR LAPSE RATES
   PROFILES...AND RELATIVE WARM NOSE ABOVE 700 MB. THUS...ALTHOUGH
   SURFACE BASED INSTABILITY WILL EXIST...UPDRAFTS MAY NOT BE
   PARTICULARLY STRONG. THUS HAVE REMOVED SLIGHT RISK BUT WILL MAINTAIN
   LOW PROBABILITIES FOR ISOLATED WIND OR HAIL.
   
   ...NW TX/WRN OK...
   BENEATH THE PLAINS RIDGE...A WEAK UPPER LOW IS FORECAST TO DRIFT
   NEWD OUT OF THE TX PANHANDLE TONIGHT AND INTO OK...PROVIDING THE
   IMPETUS FOR ISOLATED THUNDERSTORMS. WITH WARM AND DRY SUB CLOUD
   LAYERS...A FEW MICROBURSTS MAY OCCUR.
   
   ..JEWELL/GARNER.. 07/12/2011
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z