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 301625
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1125 AM CDT THU JUN 30 2011
   
   VALID 301630Z - 011200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CNTRL ROCKIES THROUGH
   NRN PLAINS INTO UPPER GREAT LAKES...
   
   ...CNTRL ROCKIES INTO NRN/CNTRL HIGH PLAINS...
   
   POTENT VORTICITY MAXIMUM OVER SWRN UT WILL PROGRESS ENEWD ACROSS THE
   REGION THROUGH THE D1 PERIOD WITH A CORRIDOR OF MODEST HEIGHT FALLS
   AND 40-50+ KT FLOW AT 500 MB ATTENDING THIS SYSTEM.  12Z REGIONAL
   SOUNDINGS SHOWED THE PRESENCE OF A STEEP LAPSE RATE ENVIRONMENT
   PRECEDING THE VORTICITY MAXIMUM AND ASSOCIATED SURFACE COLD FRONT
   WITH DAYTIME HEATING AND PW VALUES OF 0.70-0.90 INCH SUPPORTING
   AFTERNOON MLCAPE OF 1000-1500 J/KG.  ZONE OF DEEP-LAYER FORCING FOR
   ASCENT PRECEDING MIDLEVEL SYSTEM COUPLED WITH PACIFIC FRONT AND
   TERRAIN INFLUENCES WILL SUPPORT UPSCALE GROWTH OF ONGOING STORMS
   INTO MULTIPLE BANDS CAPABLE OF DAMAGING WINDS AND HAIL.
   
   EXPECT STORMS TO RAPIDLY MOVE/DEVELOP EWD/NEWD THROUGH THE CNTRL
   ROCKIES INTO NRN/CNTRL HIGH PLAINS THIS AFTERNOON INTO TONIGHT WITH
   A CONTINUED RISK FOR MAINLY DAMAGING WINDS AND HAIL.
   
   FOR ADDITIONAL NEAR TERM GUIDANCE...SEE WW 576.
   
   ...ERN DAKOTAS INTO UPPER MS VALLEY...
   
   12Z SOUNDINGS OVER THE DAKOTAS SHOWED A UNIFORMLY STRONG CAP IN
   PLACE AT THE BASE OF AN EML WHICH SHOULD SPREAD EWD ACROSS THE UPPER
   MS VALLEY TODAY GIVEN THE LARGE-SCALE AIRFLOW REGIME.  THIS CAP
   COUPLED WITH INCREASING HIGH CLOUDS FROM THE W/SW --AND THEIR
   POTENTIAL IMPACTS ON DAYTIME HEATING-- WILL LIKELY DELAY THE
   DEVELOPMENT OF SURFACE-BASED STORM DEVELOPMENT ALONG COLD FRONT
   WHERE AIR MASS WILL BECOME MODERATELY TO EXTREMELY UNSTABLE WITH
   MLCAPE OF 2000-4000+ J/KG.
   
   LATEST CONVECTION-ALLOWING AND MESOSCALE MODEL GUIDANCE SUGGESTS
   THAT TSTMS WILL BECOME INCREASINGLY LIKELY BY 01/00Z OVER NWRN MN
   INTO ERN ND/NERN SD ON THE FRINGE OF THE STRONGER CAP. 
   HERE...FORECAST HODOGRAPHS EXHIBIT VERTICALLY VEERING WIND PROFILES
   WITH 30-40 KT OF DEEP-LAYER SHEAR WHICH WILL SUPPORT SUPERCELLS
   GIVEN THE DEGREE OF INSTABILITY.  WHILE VERY LARGE HAIL WILL BE THE
   PRIMARY HAZARD...A TORNADO OR TWO IS POSSIBLE IN ADDITION TO
   DAMAGING WINDS.  THE NOCTURNAL STRENGTHENING OF A SWLY LLJ MAY
   PROMOTE THE UPSCALE GROWTH OF STORMS INTO A FORWARD-PROPAGATING MCS
   WITH A CONTINUED THREAT FOR DAMAGING WINDS AND HAIL SPREADING SEWD
   ACROSS NRN MN LATE TONIGHT INTO FRI MORNING.
   
   ...WI/MI/IND...
   
   A BAND OF ELEVATED STORMS HAS RECENTLY FORMED OVER THE WRN UP OF MI
   INTO NERN WI ALONG THE EDGE OF THE CAP AND AT TERMINUS OF DIURNALLY
   WEAKENING LLJ.  THERE IS SOME QUESTION AS TO WHETHER THIS ACTIVITY
   WILL PERSIST TODAY GIVEN THE WEAKENING LOW-LEVEL WAA/ISENTROPIC
   ASCENT WITH TIME.  BUT...GIVEN THE VERY STEEP MIDLEVEL LAPSE RATES
   AND POTENTIALLY STRONG ELEVATED INSTABILITY UPSTREAM /REF. 12Z MPX
   SOUNDING/...HAIL WILL BE POSSIBLE WITH STORMS THAT CAN PERSIST.  
   
   TONIGHT...AS MENTIONED ABOVE...EXPECT THE POTENTIAL FOR MCS
   FORMATION TO INCREASE ACROSS PARTS OF NRN WI AND THE UP OF MI WITH
   ADDITIONAL MORE ELEVATED TSTM ACTIVITY POSSIBLE DOWNSTREAM ACROSS
   LOWER MI INTO IND IN RESPONSE TO STRENGTHENING NOCTURNAL LLJ.  THESE
   STORMS WILL BE CAPABLE OF LOCALLY DAMAGING WINDS AND HAIL INTO FRI
   MORNING.
   
   ...SRN GA/NRN FL...
   
   STALLED SYNOPTIC FRONT AND DEVELOPING SEA BREEZE CIRCULATIONS WILL
   FOCUS NUMEROUS STORMS TODAY WITHIN A HIGH-PW AIR MASS WITH THE
   POTENTIAL FOR WET MICROBURST ACTIVITY OWING TO WATER LOADING
   EFFECTS.
   
   ...PORTIONS OF LOWER MS VALLEY INTO ERN OK/WRN AR...
   
   WRN EXTENSION OF STALLED SURFACE FRONT ARCING NNWWD THROUGH THE
   REGION MAY SERVE AS THE FOCUS FOR ISOLATED DIURNAL STORM
   DEVELOPMENT.  THE PRESENCE OF A MOIST BOUNDARY LAYER AND STEEPENING
   MIDLEVEL LAPSE RATES WITH NWD EXTENT WILL YIELD A MODERATELY TO
   STRONGLY UNSTABLE AIR MASS BY AFTERNOON WITH MLCAPE OF 1000-2000
   J/KG SOUTH TO 2000-3500 J/KG NORTH.  WHILE VERTICAL SHEAR WILL
   REMAIN RELATIVELY WEAK...THE POTENTIAL FOR SOME HAIL AND LOCALLY
   DAMAGING WINDS WILL BE POSSIBLE GIVEN THE FAVORABLE THERMODYNAMIC
   ENVIRONMENT.
   
   ...DEEP S TX...
   
   NRN FRINGES OF T.S. ARLENE WILL CONTINUE TO AFFECT AREA TODAY WITH A
   SMALL RISK FOR A BRIEF TORNADO WITH LAND-FALLING RAINBANDS.
   
   ..MEAD/COHEN.. 06/30/2011
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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