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Day 4-8 Severe Weather Outlook Issued on Nov 2, 2017
Updated: Thu Nov 2 08:43:04 UTC 2017
Day 4-8 Severe Weather Outlook Graphics Issued on Nov 2, 2017
Day 4 Severe Weather Outlook Graphics Issued on Nov 2, 2017
Day 4 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
30 % 47,013 7,545,089 Indianapolis, IN...Fort Wayne, IN...South Bend, IN...Gary, IN...Hammond, IN...
15 % 105,501 32,662,611 Chicago, IL...Detroit, MI...Columbus, OH...Cleveland, OH...St. Louis, MO...
Day 5 Severe Weather Outlook Graphics Issued on Nov 2, 2017
Day 5 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Day 6 Severe Weather Outlook Graphics Issued on Nov 2, 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 2, 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 2, 2017
Day 8 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
D4Sun, Nov 05, 2017 - Mon, Nov 06, 2017 D7Wed, Nov 08, 2017 - Thu, Nov 09, 2017
D5Mon, Nov 06, 2017 - Tue, Nov 07, 2017 D8Thu, Nov 09, 2017 - Fri, Nov 10, 2017
D6Tue, Nov 07, 2017 - Wed, Nov 08, 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 020841
   SPC AC 020841

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0341 AM CDT Thu Nov 02 2017

   Valid 051200Z - 101200Z

   ...DISCUSSION...
   Although model timing differences exist, trends continue to point to
   severe thunderstorms capable of large hail, damaging wind and
   isolated tornadoes on Sun/D4, roughly from Illinois into Ohio. A
   broad area of cyclonic flow aloft with dual/parallel shortwave
   troughs will affect the upper and middle MS Valleys, and points east
   including the Great Lakes region. Some early day storms may exist
   across the region as southerly winds create lift near a warm front,
   but the main severe weather threat will be near the surface low and
   cold front as it sweeps eastward from Sunday afternoon into Monday
   morning. Cold temperatures aloft, a capping inversion over the warm
   sector and long hodographs suggest supercells may be the dominant
   storm mode, creating damaging hail and wind. A few tornadoes will
   also be possible given a 50 kt low-level jet, and most likely with
   any supercells that can track eastward along the intersection of the
   cold front and warm front/outflow boundary.

   By Mon/D5, the cold front will continue across the Northeast, but
   with much less instability to work with. However, numerous storms
   and modest wind fields suggest at least some marginal wind damage
   potential. Beyond D5, model solutions diverge rapidly with a
   progressive pattern persisting.

   ..Jewell.. 11/02/2017

   CLICK TO GET WUUS48 PTSD48 PRODUCT
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Page last modified: November 02, 2017
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