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Day 4-8 Severe Weather Outlook Issued on Sep 3, 2017
Updated: Sun Sep 3 08:10:04 UTC 2017
Day 4-8 Severe Weather Outlook Graphics Issued on Sep 3, 2017
Day 4 Severe Weather Outlook Graphics Issued on Sep 3, 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 Sep 3, 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 Sep 3, 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 Sep 3, 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 Sep 3, 2017
Day 8 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
D4Wed, Sep 06, 2017 - Thu, Sep 07, 2017 D7Sat, Sep 09, 2017 - Sun, Sep 10, 2017
D5Thu, Sep 07, 2017 - Fri, Sep 08, 2017 D8Sun, Sep 10, 2017 - Mon, Sep 11, 2017
D6Fri, Sep 08, 2017 - Sat, Sep 09, 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 030808
   SPC AC 030808

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0308 AM CDT Sun Sep 03 2017

   Valid 061200Z - 111200Z

   ...DISCUSSION...
   Amplified western CONUS ridge/eastern CONUS trough pattern is
   expected at the beginning of the extended period -- i.e.
   D4/Wednesday. Guidance is in good agreement that the pattern will
   begin to lose amplitude on D5/Thursday and D6/Friday. A slow
   shortwave trough is expected to move into and through the Pacific
   Northwest on D5/Thursday and D6/Friday, leading to the breakdown of
   the persistent western CONUS ridging. Farther east, a series of
   shortwave troughs rotating through the eastern CONUS troughing will
   encourage slow northeastward progression of the parent upper trough.
   Generally weak flow aloft is anticipated across the Lower 48 this
   weekend with surface high pressure centered over the Upper Great
   Lakes dominating the sensible weather for areas east of the Rockies.

   ..Mosier.. 09/03/2017

   CLICK TO GET WUUS48 PTSD48 PRODUCT
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Page last modified: September 03, 2017
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