Jul 26, 2015 1630 UTC Day 1 Convective Outlook
Updated: Sun Jul 26 16:30:12 UTC 2015 (20150726 1630Z Day 1 shapefile | 20150726 1630Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20150726 1630 UTC Day 1 Outlook Graphic
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
SLIGHT 23,387 102,856 Garden City, KS...Lamar, CO...
MARGINAL 402,422 32,522,769 Indianapolis, IN...Columbus, OH...Boston, MA...Pittsburgh, PA...Cincinnati, OH...
Probabilistic Tornado Graphic
20150726 1630 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.
Day 1 Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Damaging Wind Graphic
20150726 1630 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.
Day 1 Wind Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
15 % 23,387 102,856 Garden City, KS...Lamar, CO...
5 % 401,043 32,222,055 Indianapolis, IN...Columbus, OH...Boston, MA...Pittsburgh, PA...Cincinnati, OH...
Probabilistic Large Hail Graphic
20150726 1630 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.
Day 1 Hail Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
5 % 336,268 15,911,510 Boston, MA...Worcester, MA...Springfield, MA...Hartford, CT...Cedar Rapids, IA...
   SPC AC 261630

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1130 AM CDT SUN JUL 26 2015

   VALID 261630Z - 271200Z

   ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE CNTRL HIGH PLAINS...

   ...THERE IS A MRGL RISK OF SVR TSTMS OVER THE NRN AND CNTRL HIGH
   PLAINS...

   ...THERE IS A MRGL RISK OF SVR TSTMS FROM THE MIDWEST/NORTH OF OH
   VALLEY TO ALLEGHENY PLATEAU TO THE NORTHEAST...

   ...THERE IS A MRGL RISK OF SVR TSTMS OVER THE NRN ROCKIES/WRN-CNTRL
   MT...

   ...SUMMARY...
   WIDELY SCATTERED STRONG TO SEVERE THUNDERSTORMS ARE EXPECTED MAINLY
   THIS AFTERNOON AND EVENING ACROSS PORTIONS OF THE HIGH
   PLAINS...MIDDLE MISSISSIPPI/LOWER OHIO VALLEYS...AND NORTHEAST
   STATES.

   ...CNTRL/NRN HIGH PLAINS...
   MORNING SATELLITE IMAGERY DEPICTS MOSTLY CLEAR SKIES ACROSS THE HIGH
   PLAINS FROM THE RIO GRANDE TO CANADIAN BORDER. DIURNAL
   HEATING/MIXING AND WEAK BACKGROUND ASCENT/HEIGHT FALLS FROM ERN CO
   NWD SHOULD CONTRIBUTE TO WIDELY SCATTERED CONVECTIVE INITIATION
   ALONG/AHEAD OF HIGH PLAINS LEE/THERMAL TROUGH LATER THIS AFTERNOON.
   DESPITE VERY WARM MID-LEVEL TEMPS DELINEATING LOWER LAYER OF EML
   PLUME...DEEPER BOUNDARY LAYER MIXING/HEATING SHOULD BE ABLE TO AID
   IN OVERCOMING CONVECTIVE INHIBITION WITH AT LEAST A FEW STORMS ABLE
   TO TAP INTO STRONG SURFACE-BASED INSTABILITY. EFFECTIVE SHEAR ON THE
   ORDER OF 25-30KT SHOULD SUPPORT A COUPLE OF MORE PERSISTENT STORM
   UPDRAFTS/SUPERCELLS WITH THE CAPABILITY OF PRODUCING HAIL AND HIGH
   WINDS. SOMEWHAT GREATER STORM COVERAGE AND PERSISTENCE MAY EXIST
   ACROSS ERN CO WHERE STORMS MAY DRIFT TOWARD AXIS OF GREATER LOW
   LEVEL MOISTURE/DESTABILIZATION ALONG THE CO/KS BORDER WITH TIME.
   SOME OF THIS ACTIVITY MAY ALSO PERSIST INTO THE NIGHTTIME HOURS AS
   MASS TRANSPORT AND LOW LEVEL ASCENT ARE MAXIMIZED ON THE NOSE OF
   PLAINS LLJ.

   ...MIDWEST/TO NORTH OF OH VALLEY/ALLEGHENY PLATEAU...
   FORECAST IS COMPLICATED ACROSS THE MIDWEST GIVEN THE DECAYING
   REMNANTS OF A PAIR OF OVERNIGHT MCS/S...ONE NOW CROSSING THE LOWER
   OH RIVER VALLEY IN WRN KY AND THE MO BOOTHEEL...THE OTHER MOVING
   INTO WRN IL FROM SERN IA AND ERN MO. NRN SYSTEM APPEARS TO BE
   ASSOCIATED WITH A RELATIVELY STRONG SHORTWAVE TROUGH EVIDENT ON
   WATER VAPOR SATELLITE IMAGERY OVER MN/IA...AND A PACKET OF STRONGER
   30-35 KT MIDLEVEL FLOW PER REGIONAL VWP OBSERVATIONS.

   STRONG HEATING IN THE WAKE OF THE SHORTWAVE/MCV ACROSS MN/IA WILL
   CONTRIBUTE TO AN AXIS OF STRONG INSTABILITY ALONG THE EDGE OF THE
   PLAINS CAPPING INVERSION/EML. WHILE LARGE SCALE SUPPORT FOR ASCENT
   WILL PROBABLY BE WANING ALONG THIS CORRIDOR...A CONDITIONAL SEVERE
   HAIL/WIND RISK WILL BE MAINTAINED IN THE EVENT ISOLATED STORMS CAN
   DEVELOP GIVEN CONTINUING LOW LEVEL CONVERGENCE ALONG RESIDUAL FRONT
   AND OUTFLOW BOUNDARIES REMAINING IN THE PRESENCE OF STRONG TO
   LOCALLY EXTREME DESTABILIZATION.

   FARTHER EAST....FROM IND TO PA...INSTABILITY AND WEAK LIFT WILL BE
   FOCUSED ALONG THE STALLED FRONT SITUATED ACROSS THESE AREAS. A FEW
   AFTERNOON OR EARLY EVENING STORMS COULD RESULT IN LOCALLY STRONG
   GUSTS AND PERHAPS A COUPLE OF TREE-DOWN EVENTS.

   ...NORTHEAST...
   MODEST WARM SECTOR DESTABILIZATION WAS UNDERWAY WITH LATEST
   OBJECTIVE DATA INDICATING MLCAPE OF AROUND 1000 J/KG ACROSS MUCH OF
   NY AND LITTLE IN THE WAY OF INHIBITION. LARGE SCALE PATTERN ACROSS
   NEW ENGLAND IS MARGINALLY SUPPORTIVE OF SEVERE STORMS IF STORMS CAN
   DEVELOP WITHIN THE WARM SECTOR...AND NEAR/ALONG CT RIVER VALLEY WARM
   FRONT LATER THIS AFTERNOON. NWLY FLOW AT MIDLEVELS AND WEAK SLY/SELY
   FLOW NEAR THE SURFACE WILL RESULT IN LOCALLY SUFFICIENT SHEAR FOR A
   FEW STRONGER UPDRAFTS CAPABLE OF GUSTY WINDS AND PERHAPS SOME HAIL.
   MAIN LIMITING FACT IS THE LACK OF STRONGER DEEP-LAYER ASCENT AS
   PRIMARY SHORTWAVE TROUGH APPEARS TO BE CROSSING THE REGION NOW
   FOLLOWED BY NEUTRAL TO WEAK HEIGHT RISES AROUND THE TIME OF MAXIMUM
   STORM INITIATION POTENTIAL. NONETHELESS...IF STORMS CAN
   DEVELOP...THERE MAY EVOLVE A BRIEF PERIOD OF SEVERE WEATHER IN THE
   FORM OF MARGINALLY STRONG WIND GUSTS AND HAIL LATER THIS AFTERNOON.

   ...NRN ROCKIES...
   AN AMPLIFYING MID/UPPER TROUGH ACROSS BC AND THE PACIFIC NORTHWEST
   WILL SUPPORT THE INTENSIFICATION OF A SWLY MID/UPPER JET ACROSS THE
   NRN ROCKIES THIS PERIOD. HEATING ACROSS THE HIGHER TERRAIN SHOULD
   AID IN CONVECTIVE INITIATION LATER THIS AFTERNOON GIVEN DECREASING
   STATIC STABILITY AND SUFFICIENT MOISTURE TO SUPPORT MLCAPE ON THE
   ORDER OF 500 J/KG. WITH MEAN WIND AROUND 50KT AND MODEST DIRECTIONAL
   SHEAR AROUND CLOUD BASE THERE IS THE POSSIBILITY FOR A FEW
   FAST-MOVING LOW-TOPPED SUPERCELLS WITH SOME CHANCE FOR HAIL AROUND
   AN INCH AND LOCALLY NEAR-SEVERE WIND GUSTS.

   ..CARBIN/GLEASON.. 07/26/2015

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