Aug 24, 2016 0730 UTC Day 3 Severe Thunderstorm Outlook
Updated: Wed Aug 24 05:46:54 UTC 2016 (20160824 0730Z Day 3 shapefile | 20160824 0730Z Day 3 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
0730 UTC Day 3 Outlook Graphic
Day 3 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
MARGINAL 69,887 403,416 Rapid City, SD...Scottsbluff, NE...Pierre, SD...Sterling, CO...Spearfish, SD...
Probabilistic Graphic
20160824 0730 UTC Day Probabilitic Graphic
Probability of severe weather within 25 miles of a point.
Hatched Area: 10% or greater probability of significant severe within 25 miles of a point.
Day 3 Prob. Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
5 % 68,567 400,169 Rapid City, SD...Scottsbluff, NE...Pierre, SD...Sterling, CO...Spearfish, SD...
   SPC AC 240546

   DAY 3 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1246 AM CDT WED AUG 24 2016

   VALID 261200Z - 271200Z

   ...THERE IS A MRGL RISK OF SVR TSTMS ACROSS ERN WY...WRN SD AND WRN
   NEB...

   ...SUMMARY...
   A FEW MARGINALLY SEVERE STORMS ARE EXPECTED ACROSS THE NORTHERN HIGH
   PLAINS...WITH A LARGE AREA OF GENERAL THUNDERSTORMS FROM THE ROCKIES
   INTO THE MID MISSISSIPPI AND OHIO VALLEYS. A STRONG STORM OR TWO
   WITH WIND MAY OCCUR ACROSS MAINE AS WELL.

   ...SYNOPSIS...
   A BROAD UPPER TROUGH WILL MOVE QUICKLY ACROSS ERN CANADA WITH BASE
   OF THE TROUGH AFFECTING NEW ENGLAND WITH STRONG WINDS ALOFT. A LOW
   PRESSURE TROUGH WILL ALSO MOVE ACROSS MAINE DURING THE DAY...AND MAY
   FOCUS A FEW THUNDERSTORMS. MEANWHILE...AN UPPER HIGH WILL REMAIN
   SITUATED OVER THE SERN U.S. WITH BUILDING HEIGHTS OVER THE NE.

   TO THE W...A BROAD UPPER TROUGH WILL MOVE INTO THE NRN PLAINS WITH
   COOL AIR ALOFT AND SOME INCREASE IN WIND SPEEDS. WITH HIGH PRESSURE
   CENTERED OVER THE GREAT LAKES...SLY FLOW WILL EVENTUALLY BRING
   MOISTURE NWWD TOWARD THE NRN HIGH PLAINS LATE IN THE DAY WHERE A LEE
   TROUGH WILL PROVIDE A FOCUS FOR A FEW SEVERE STORMS.

   ...ERN WY...WRN SD AND WRN NEB...
   RELATIVELY COOL TEMPERATURES ALOFT WILL EXIST BENEATH THE UPPER
   TROUGH AND HEATING WILL CREATE STEEP LOW LEVEL LAPSE RATES AS WELL
   OVER WRN SD/NEB AND ERN WY. HERE...SELY SFC WINDS LIKELY BRING 50S F
   DEWPOINTS NWWD TOWARD A WEAK SFC TROUGH BY AFTERNOON...RESULTING IN
   AROUND 1000 J/KG MUCAPE. LOW-LEVEL FLOW WILL BE WEAK...BUT GOOD MID
   TO UPPER LEVEL FLOW WILL LENGTHEN HODOGRAPHS AND RESULT IN A
   FAVORABLE ENVIRONMENT FOR A FEW SPLITTING CELLS CAPABLE OF
   MARGINALLY SEVERE HAIL. SOME STORMS WILL PERSIST ACROSS CNTRL SD/NEB
   DURING THE EVENING...BUT MOSTLY A RAIN THREAT IS EXPECTED AT THAT
   TIME.

   ...MAINE...
   A LOW-AMPLITUDE UPPER TROUGH WILL GRAZE THE AREA WITH SFC TROUGH
   MOVING ACROSS NRN NEW ENGLAND DURING THE DAY. INSTABILITY SHOULD BE
   SUFFICIENT FOR A FEW STRONG STORMS GIVEN FORCING FOR ASCENT AND
   INCREASED MEAN DEEP-LAYER WIND SPEEDS. HOWEVER...MODELS VARY WITH
   QPF SIGNAL ACROSS THE AREA AND PREDICTABILITY IS CURRENTLY TOO LOW
   TO INTRODUCE A MARGINAL RISK.

   ..JEWELL.. 08/24/2016

   NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z