Mar 31, 2015 0730 UTC Day 3 Severe Thunderstorm Outlook
Updated: Tue Mar 31 13:23:04 UTC 2015 (20150331 0730Z Day 3 shapefile | 20150331 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
SLIGHT 134,057 14,326,554 Dallas, TX...Memphis, TN...Tulsa, OK...Arlington, TX...St. Louis, MO...
MARGINAL 183,214 30,707,390 Detroit, MI...Indianapolis, IN...Columbus, OH...Fort Worth, TX...Nashville, TN...
Probabilistic Graphic
20150331 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
15 % 134,056 14,138,420 Dallas, TX...Memphis, TN...Tulsa, OK...Arlington, TX...St. Louis, MO...
5 % 182,745 30,847,437 Detroit, MI...Indianapolis, IN...Columbus, OH...Fort Worth, TX...Nashville, TN...
   SPC AC 311323

   DAY 3 CONVECTIVE OUTLOOK CORR 1
   NWS STORM PREDICTION CENTER NORMAN OK
   0823 AM CDT TUE MAR 31 2015

   VALID 021200Z - 031200Z

   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE LOWER OH/MID MS
   VALLEYS WSWWD INTO ERN OK/NERN TX...

   ...THERE IS A MRGL RISK OF SVR TSTMS FROM OH/LOWER MI WSWWD INTO THE
   SRN PLAINS...

   CORRECTED FOR NDFD/PROB LINES

   ...SUMMARY...
   SHOWERS AND THUNDERSTORMS ARE FORECAST FROM THE GREAT LAKES AREA
   SOUTHWESTWARD INTO THE OZARKS AND ADJACENT EASTERN
   OKLAHOMA/NORTHEAST TEXAS.  HAIL AND LOCALLY DAMAGING WINDS WILL BE
   POSSIBLE WITH THESE STORMS -- PARTICULARLY FROM THE LOWER OHIO AND
   MID MISSISSIPPI VALLEYS SOUTHWESTWARD.

   ...SYNOPSIS...
   EWD PROGRESSION OF AN UPPER TROUGH EXITING THE ROCKIES WILL CONTINUE
   THIS PERIOD...FLATTENING/DEAMPLIFYING AS IT SPREADS ACROSS THE GREAT
   LAKES REGION DURING THE SECOND HALF OF THE PERIOD.  BY THE END OF
   THE PERIOD...FAST -- BUT RELATIVELY LOW-AMPLITUDE -- CYCLONIC FLOW
   SHOULD COVER MUCH OF THE CONUS.

   AT THE SURFACE...A COLD FRONT ASSOCIATED WITH THE ADVANCING UPPER
   TROUGH IS FORECAST TO SHIFT QUICKLY EWD ACROSS THE GREAT LAKES
   REGION...AND MORE SLOWLY SEWD ACROSS THE MIDWEST/OH VALLEY AND
   OZARKS REGION.  BY LATE IN THE PERIOD...THE FRONT SHOULD STRETCH
   FROM NEW ENGLAND WSWWD ACROSS/ALONG THE OH VALLEY INTO N TX.  ONCE
   AGAIN...THIS FRONT WILL FOCUS SHOWERS AND THUNDERSTORMS -- AND SOME
   RISK FOR HAIL AND LOCALLY DAMAGING WINDS WITH STRONGER STORMS.

   ...GREAT LAKES REGION SWWD TO ERN OK/NERN TX...
   CONTINUED NEWD ADVECTION OF HIGHER-THETA E LOW-LEVEL AIR WILL
   CONTINUE AHEAD OF THE ADVANCING COLD FRONT...WITH 60S DEWPOINTS
   BECOMING WIDESPREAD AHEAD OF THE FRONT.  DIURNAL HEATING BENEATH
   STEEP MID-LEVEL LAPSE RATES WILL COMBINE WITH THE INCREASING
   MOISTURE TO BOOST AFTERNOON MIXED-LAYER CAPE VALUES INTO THE 1500 TO
   2500 J/KG RANGE FROM THE MID MS VALLEY WSWWD...AND AOA 500 J/KG AS
   FAR NEWD AS LOWER MI AND THE LOWER GREAT LAKES REGION.

   WHILE SOME CONVECTION SHOULD LINGER THROUGH THE MORNING ACROSS THE
   LOWER MO/MID MS VALLEY AREA...EXPECT STORMS TO DIURNALLY INCREASE
   ALONG THE FRONT FROM LOWER MI SWWD INTO THE OZARKS/ERN OK AND
   ADJACENT NERN TX.  WITH THE MID-LEVEL FLOW FIELD PROGGED TO
   STRENGTHEN WITH TIME ACROSS THIS REGION...ORGANIZED/LOCALLY SEVERE
   STORMS WILL LIKELY EVOLVE.  WITH LOW-LEVEL FLOW LIKELY BE SOMEWHAT
   VEERED AHEAD OF THE FRONT THUS REDUCING DIRECTIONAL SHEAR...AND WITH
   FLOW ALOFT BECOMING INCREASINGLY ALIGNED ALONG THE
   FRONT...MESSY/MAINLY LINEAR STORM MODES ARE ANTICIPATED.  MAIN
   SEVERE RISKS SHOULD BE HAIL AND LOCALLY GUSTY/DAMAGING WINDS --
   PRIMARILY THROUGH EARLY EVENING -- THOUGH WIDESPREAD CONVECTION WILL
   LIKELY CONTINUE THROUGH THE OVERNIGHT HOURS INVOF THE SLOWLY SAGGING
   FRONT.

   ..GOSS.. 03/31/2015

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