Day 1 Outlook Day 2 Outlook Day 3 Outlook Days 4-8 Outlook

Day 4-8 Outlook
Day 4 - 8 Outlook
Day 4-8 Severe Weather Outlook. A depicted severe weather area indicates a 30% or higher probability for severe thunderstorms within 25 miles of a point.
D4Thu, Sep 27, 2018 - Fri, Sep 28, 2018 D7Sun, Sep 30, 2018 - Mon, Oct 01, 2018
D5Fri, Sep 28, 2018 - Sat, Sep 29, 2018 D8Mon, Oct 01, 2018 - Tue, Oct 02, 2018
D6Sat, Sep 29, 2018 - Sun, Sep 30, 2018 (All days are valid from 12 UTC - 12 UTC)
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. 1) large differences in the deterministic model solutions,
  2. 2) large spread in the ensemble guidance, and/or
  3. 3) minimal run-to-run continuity.
POTENTIAL TOO LOW means the threat for a regional area of organized severe storms appears highly unlikely during the entire period (e.g. less than a 30% probability for a regional severe storm area across the CONUS through the entire Day 4-8 period).

Images courtesy of the NWS Storm Prediction Center
 Forecast Discussion


000
ACUS48 KWNS 240830
SWOD48
SPC AC 240829

Day 4-8 Convective Outlook  
NWS Storm Prediction Center Norman OK
0329 AM CDT Mon Sep 24 2018

Valid 271200Z - 021200Z

...DISCUSSION...
The latest medium-range model runs exhibit remarkable similarity
through the day 6/day 7 time frame, after which some deviation
begins to increase with respect to the large-scale flow pattern
across the country.  Prior to that, however, pattern evolution
suggests limited severe weather risk CONUS-wide, as a long-wave
trough -- whose broad cyclonic flow field will encompass much of the
U.S. initially -- gradual weakens and retreats northward into
Canada.  In its wake, a much more weakly cyclonic -- trending toward
zonal -- flow field is expected to evolve, downstream of a blocking
pattern over Alaska and the eastern Pacific.  Given the lack of
apparent/substantial severe risk at this time, no outlook areas will
be issued.

..Goss.. 09/24/2018