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Day 4-8 Severe Weather Outlook Issued on Nov 1, 2017
Updated: Wed Nov 1 08:54:02 UTC 2017
Day 4-8 Severe Weather Outlook Graphics Issued on Nov 1, 2017
Day 4 Severe Weather Outlook Graphics Issued on Nov 1, 2017
Day 4 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Day 5 Severe Weather Outlook Graphics Issued on Nov 1, 2017
Day 5 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
15 % 131,756 32,449,930 Chicago, IL...Detroit, MI...Indianapolis, IN...Milwaukee, WI...St. Louis, MO...
Day 6 Severe Weather Outlook Graphics Issued on Nov 1, 2017
Day 6 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Day 7 Severe Weather Outlook Graphics Issued on Nov 1, 2017
Day 7 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Day 8 Severe Weather Outlook Graphics Issued on Nov 1, 2017
Day 8 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
D4Sat, Nov 04, 2017 - Sun, Nov 05, 2017 D7Tue, Nov 07, 2017 - Wed, Nov 08, 2017
D5Sun, Nov 05, 2017 - Mon, Nov 06, 2017 D8Wed, Nov 08, 2017 - Thu, Nov 09, 2017
D6Mon, Nov 06, 2017 - Tue, Nov 07, 2017 (All days are valid from 12 UTC - 12 UTC the following day)
Note: A severe weather area depicted in the Day 4-8 period indicates 15%, 30% or higher probability for severe thunderstorms within 25 miles of any point.
PREDICTABILITY TOO LOW is used to indicate severe storms may be possible based on some model scenarios. However, the location or occurrence of severe storms are in doubt due to: 1) large differences in the deterministic model solutions, 2) large spread in the ensemble guidance, and/or 3) minimal run-to-run continuity.
POTENTIAL TOO LOW means the threat for a regional area of organized severe storms appears unlikely (i.e., less than 15%) for the forecast day.
 Forecast Discussion

   ZCZC SPCSWOD48 ALL
   ACUS48 KWNS 010851
   SPC AC 010851

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0351 AM CDT Wed Nov 01 2017

   Valid 041200Z - 091200Z

   ...DISCUSSION...
   Substantial height falls will occur across the Plains and into the
   Midwest on Sun/D5 with parallel shortwave troughs. The strongest
   wave will move across the northern Plains, with the secondary one
   across the central Plains into the Midwest. At the surface, a cold
   front will extend roughly from MI into MO and OK, with the
   possibility of mid 60s dewpoints ahead of it and MUCAPE values in
   excess of 1500 J/kg. This may result in severe thunderstorms from IL
   and southern WI across lower MI and IN Sunday and Sunday night. The
   main threat will be large hail and damaging winds with long
   hodographs and steep lapse rates aloft. Both supercell and linear
   storm modes will be possible.

   By Mon/D6, the main upper trough will rapidly progress into Quebec,
   with a cold front moving across the Northeast. By this time,
   instability will be quite weak, but scattered storms and some minor
   wind threat appears likely.

   ..Jewell.. 11/01/2017

   CLICK TO GET WUUS48 PTSD48 PRODUCT
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Page last modified: November 01, 2017
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