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Day 4-8 Severe Weather Outlook Issued on Sep 7, 2017
Updated: Thu Sep 7 08:41:02 UTC 2017
Day 4-8 Severe Weather Outlook Graphics Issued on Sep 7, 2017
Day 4 Severe Weather Outlook Graphics Issued on Sep 7, 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 7, 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 7, 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 7, 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 7, 2017
Day 8 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
D4Sun, Sep 10, 2017 - Mon, Sep 11, 2017 D7Wed, Sep 13, 2017 - Thu, Sep 14, 2017
D5Mon, Sep 11, 2017 - Tue, Sep 12, 2017 D8Thu, Sep 14, 2017 - Fri, Sep 15, 2017
D6Tue, Sep 12, 2017 - Wed, Sep 13, 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 070839
   SPC AC 070839

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0339 AM CDT Thu Sep 07 2017

   Valid 101200Z - 151200Z

   ...DISCUSSION...
   Primary feature of interest during the extended period is Hurricane
   Irma. Irma is expected to make a northeasterly turn but model
   consensus regarding when and where the turn occurs is poor. This
   forecast uncertainty combined with typical uncertainties regarding
   tropical cyclone tornado environments results in low predictability.
   Official forecasts and the most up-to-date information regarding
   Irma can be found through the National Hurricane Center.

   Elsewhere, upper ridging centered over the central Rockies on
   D4/Sunday will persist through at least D6/Tuesday while an upper
   low remains nearly stationary off the southern/central CA coast. The
   persistence of these two features will displace any strong westerly
   flow aloft north of the US/Canada border through at least the middle
   of next week. Long-range guidance is beginning to show a more
   progressive trough by the end of next week but given the forecast
   range and run-to-run/model-to-model variability forecast confidence
   is low.

   ..Mosier.. 09/07/2017

   CLICK TO GET WUUS48 PTSD48 PRODUCT
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Page last modified: September 07, 2017
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