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Day 4-8 Severe Weather Outlook Issued on Sep 5, 2017
Updated: Tue Sep 5 08:33:03 UTC 2017
Day 4-8 Severe Weather Outlook Graphics Issued on Sep 5, 2017
Day 4 Severe Weather Outlook Graphics Issued on Sep 5, 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 5, 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 5, 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 5, 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 5, 2017
Day 8 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
D4Fri, Sep 08, 2017 - Sat, Sep 09, 2017 D7Mon, Sep 11, 2017 - Tue, Sep 12, 2017
D5Sat, Sep 09, 2017 - Sun, Sep 10, 2017 D8Tue, Sep 12, 2017 - Wed, Sep 13, 2017
D6Sun, Sep 10, 2017 - Mon, Sep 11, 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 050831
   SPC AC 050831

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0331 AM CDT Tue Sep 05 2017

   Valid 081200Z - 131200Z

   ...DISCUSSION...
   Primary feature of interest during the extended period is Hurricane
   Irma, which could begin impacting portions of FL as early as
   D4/Friday. Guidance is in very good agreement through D4/Friday, but
   given the typical uncertainties regarding the track and strength of
   tropical systems and the mesoscale sensitivities tropical cyclone
   tornado environments, it is too early to indicate any tornado
   threat. Refer to National Hurricane Center for the latest forecast
   details on Hurricane Irma.

   Surface lee troughing will persist across the High Plains on
   D4/Friday and D5/Saturday and the resultant upslope flow will 
   contribute to potential thunderstorms. However, meager low-level
   moisture and weak instability are currently anticipated, keeping
   severe probabilities low. 

   For the remainder of the period (D6/Sunday through D8/Tuesday),
   severe potential across the majority of the CONUS is low with
   Hurricane Irma likely the only feature that could result in severe
   thunderstorms.

   ..Mosier.. 09/05/2017

   CLICK TO GET WUUS48 PTSD48 PRODUCT
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Page last modified: September 05, 2017
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