Jul 25, 2014 0600 UTC Day 1 Convective Outlook
Updated: Fri Jul 25 05:37:51 UTC 2014 (20140725 1200Z Day 1 shapefile | 20140725 1200Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20140725 1200 UTC Day 1 Outlook Graphic
Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Tornado Graphic
20140725 1200 UTC Day 1 Tornado Probabilities 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.
Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
2 % 65,898 6,984,165 Minneapolis, MN...St. Paul, MN...Madison, WI...Rochester, MN...Bloomington, MN...
Probabilistic Damaging Wind Graphic
20140725 1200 UTC Day 1 Damaging Wind Probabilities 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.
Wind Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
5 % 504,820 29,883,233 Milwaukee, WI...Omaha, NE...Minneapolis, MN...St. Paul, MN...Lincoln, NE...
Probabilistic Large Hail Graphic
20140725 1200 UTC Day 1 Large Hail Probabilities 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.
Hail Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
5 % 463,130 24,827,624 Milwaukee, WI...Omaha, NE...Minneapolis, MN...St. Paul, MN...Lincoln, NE...
   SPC AC 250537

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1237 AM CDT FRI JUL 25 2014

   VALID 251200Z - 261200Z

   ...NO SVR TSTM AREAS FORECAST...

   ...SUMMARY...
   ISOLATED TO VERY WIDELY SCATTERED THUNDERSTORM ACTIVITY MAY BE
   ACCOMPANIED BY A RISK FOR LARGE HAIL AND LOCALLY STRONG WIND GUSTS
   TODAY ACROSS THE CENTRAL PLAINS INTO THE UPPER MISSISSIPPI VALLEY. 
   A FEW STRONG STORMS ALSO APPEAR POSSIBLE ACROSS THE SOUTHERN MID
   ATLANTIC COAST REGION...WITH SOME RISK FOR LOCALIZED DAMAGING WIND
   GUSTS.

   ...SYNOPSIS...
   LITTLE CHANGE TO THE LARGE-SCALE UPPER PATTERN IS EXPECTED THROUGH
   THIS FORECAST PERIOD ACROSS NORTH AMERICA.  WHILE BLOCKING REMAINS
   PROMINENT WITHIN THE WESTERLIES ACROSS THE HIGHER LATITUDES...MODELS
   INDICATE THAT SUBTROPICAL RIDGING WILL MAINTAIN STRENGTH ACROSS MUCH
   OF THE CENTRAL AND SOUTHERN TIER OF THE U.S...FROM THE PACIFIC COAST
   THROUGH THE LOWER OHIO/TENNESSEE VALLEYS AND GULF STATES.  

   WITHIN THE SOUTHERN BRANCH OF THE SPLIT WESTERLIES...AN ELONGATED
   CLOSED LOW IS FORECAST TO SHIFT SLOWLY EASTWARD OR EAST
   SOUTHEASTWARD NEAR THE CENTRAL CANADIAN/U.S. BORDER AREA. 
   CONSIDERABLE SPREAD PERSISTS AMONG THE NCEP SREF ENSEMBLE MEMBERS
   CONCERNING THE PROGRESSION OF THIS FEATURE BY LATE TONIGHT...BUT
   WEAK TO MODEST MID-LEVEL HEIGHT FALLS PROBABLY WILL SPREAD FROM THE
   NORTHERN PLAINS THROUGH MUCH OF THE UPPER MIDWEST BY LATE EVENING. 
   AN ASSOCIATED WEAK SURFACE FRONT PROBABLY WILL STALL OVER THE
   CENTRAL PLAINS...WHILE SLOWLY ADVANCING EASTWARD THROUGH THE UPPER
   MISSISSIPPI VALLEY AND UPPER MIDWEST.

   A TONGUE OF RELATIVELY MOIST AIR ALONG/AHEAD OF THIS FRONT WILL AT
   LEAST CONTRIBUTE TO THE RISK FOR THUNDERSTORM ACTIVITY TODAY FROM
   THE LEE OF THE FRONT RANGE OF THE ROCKIES THROUGH THE UPPER MIDWEST.
   HOWEVER...HIGHEST MOISTURE CONTENT AIR...AND RELATIVELY HIGHER
   THUNDERSTORM PROBABILITIES...PROBABLY WILL BE CONFINED TO THE GULF
   AND SOUTH ATLANTIC COASTS...ALONG AND SOUTH OF A WEAKENING FRONTAL
   ZONE ASSOCIATED WITH RESIDUAL UPPER TROUGHING ALONG THE ATLANTIC
   SEABOARD.

   AT THE SAME TIME...MONSOONAL MOISTURE RETURN WILL CONTINUE AROUND
   THE WESTERN PERIPHERY OF THE SOUTHERN PLAINS SUBTROPICAL HIGH
   CENTER.  AND THIS SHOULD CONTRIBUTE TO CONSIDERABLE THUNDERSTORM
   ACTIVITY ACROSS THE LOWER COLORADO VALLEY INTO THE CENTRAL ROCKIES.

   ...NORTH CENTRAL PLAINS INTO UPPER MIDWEST...
   GIVEN THE AVAILABLE MOISTURE...THE PRESENCE OF RATHER STEEP
   MID-LEVEL LAPSE RATES ASSOCIATED WITH VERY WARM ELEVATED MIXED LAYER
   AIR...CURRENTLY STILL ADVECTING ACROSS THE NORTHERN AND CENTRAL
   PLAINS TOWARD THE UPPER MIDWEST...WILL CONTRIBUTE TO AT LEAST
   CONDITIONAL SEVERE THUNDERSTORM POTENTIAL ACROSS A FAIRLY BROAD
   AREA.  HOWEVER...THIS REGIME APPEARS LIKELY TO CONTINUE TO RESULT IN
   STRONG INHIBITION OF CONVECTIVE DEVELOPMENT... PARTICULARLY ACROSS
   THE MORE MOIST PRE-FRONTAL BOUNDARY LAYER AIR MASS.  

   HIGHEST THUNDERSTORM  PROBABILITIES ACROSS THE REGION SEEM LIKELY TO
   EXIST WITHIN AN ELEVATED LAYER OF MOISTENING AND WARM ADVECTION...ON
   THE EASTERN PERIPHERY OF THE ELEVATED MIXED LAYER AIR AS IT NOSES
   INTO THE UPPER MIDWEST.  BUT MARGINAL SEVERE HAIL MAY BE THE PRIMARY
   HAZARD WITH THIS ACTIVITY.  

   THUNDERSTORMS ALSO APPEAR PROBABLE THIS AFTERNOON AND EVENING ALONG
   AND TO THE LEE OF THE FRONT RANGE OF THE ROCKIES...WHERE THE
   ENVIRONMENT MAY BE AT LEAST MARGINALLY CONDUCIVE TO SEVERE WIND
   GUSTS AND HAIL.  

   IN BETWEEN THESE TWO AREAS...DESPITE THE PROBABLE DEVELOPMENT OF
   SIZABLE MIXED LAYER CAPE ACROSS PORTIONS OF THE MID MISSOURI AND
   UPPER MISSISSIPPI VALLEY...GUIDANCE REMAINS UNCLEAR CONCERNING
   CONVECTIVE DEVELOPMENT.  FORCING MAY REMAIN TOO WEAK TO SUPPORT
   ANYTHING OTHER THAN ISOLATED TO VERY WIDELY SCATTERED STORM
   DEVELOPMENT.  ANY STORMS THAT DO FORM WILL BE ACCOMPANIED BY AT
   LEAST SOME SEVERE WEATHER POTENTIAL...PARTICULARLY ACROSS PORTIONS
   OF SOUTHERN MINNESOTA AND NORTHERN IOWA INTO WISCONSIN...WHERE
   VERTICAL SHEAR WILL BE SUFFICIENT FOR SUPERCELLS.

   ...SOUTHERN MID ATLANTIC COAST...
   DEEP LAYER WESTERLY FLOW IS FORECAST TO BECOME INCREASINGLY LIGHT
   ALONG THE WEAKENING FRONTAL ZONE ACROSS THE REGION.  BUT
   INSOLATION...IN THE PRESENCE OF SEASONABLY HIGH MOISTURE CONTENT
   AIR...MAY SUPPORT SUFFICIENT DESTABILIZATION FOR VIGOROUS CONVECTIVE
   DEVELOPMENT...WITH HEAVY PRECIPITATION LOADING CONTRIBUTING TO AT
   LEAST LOW PROBABILITIES FOR POTENTIALLY DAMAGING WIND GUSTS.

   ..KERR.. 07/25/2014

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