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Day 4-8 Severe Weather Outlook Issued on Sep 25, 2017
Updated: Mon Sep 25 07:52:02 UTC 2017
Day 4-8 Severe Weather Outlook Graphics Issued on Sep 25, 2017
Day 4 Severe Weather Outlook Graphics Issued on Sep 25, 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 25, 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 25, 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 25, 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 25, 2017
Day 8 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
D4Thu, Sep 28, 2017 - Fri, Sep 29, 2017 D7Sun, Oct 01, 2017 - Mon, Oct 02, 2017
D5Fri, Sep 29, 2017 - Sat, Sep 30, 2017 D8Mon, Oct 02, 2017 - Tue, Oct 03, 2017
D6Sat, Sep 30, 2017 - Sun, Oct 01, 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 250750
   SPC AC 250750

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0250 AM CDT Mon Sep 25 2017

   Valid 281200Z - 031200Z

   ...DISCUSSION...
   A shortwave trough will migrate southward across portions of the
   Great Lakes through D4/Thursday and D5/Friday, while a weakening
   cutoff low dissipates across the Intermountain West.  At the
   surface, an expansive ridge will spread a cooler, drier airmass of
   continental origin across much of the central and eastern CONUS,
   with deeper boundary layer moisture confined to Gulf Coast regions
   south of a stationary front in that area.  This overall pattern will
   result in a minimal severe threat through at least D7/Sunday.

   After D7, an active/amplified mid-level pattern across the northern
   tier of the U.S. may interact with returning boundary layer moisture
   on the western periphery of an anticyclone as it shifts toward the
   East Coast.  This pattern may eventually result in a returning
   severe risk to the center of the country beyond the extended
   forecast period although confidence is low.

   ..Cook.. 09/25/2017

   CLICK TO GET WUUS48 PTSD48 PRODUCT
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Page last modified: September 25, 2017
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