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Day 4-8 Severe Weather Outlook Issued on Aug 18, 2020
Updated: Tue Aug 18 08:46:03 UTC 2020
Day 4-8 Severe Weather Outlook Graphics Issued on Aug 18, 2020
Day 4 Severe Weather Outlook Graphics Issued on Aug 18, 2020
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 Aug 18, 2020
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 Aug 18, 2020
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 Aug 18, 2020
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 Aug 18, 2020
Day 8 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
D4Fri, Aug 21, 2020 - Sat, Aug 22, 2020 D7Mon, Aug 24, 2020 - Tue, Aug 25, 2020
D5Sat, Aug 22, 2020 - Sun, Aug 23, 2020 D8Tue, Aug 25, 2020 - Wed, Aug 26, 2020
D6Sun, Aug 23, 2020 - Mon, Aug 24, 2020 (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 180844
   SPC AC 180844

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0344 AM CDT Tue Aug 18 2020

   Valid 211200Z - 261200Z

   ...DISCUSSION...
   While latest runs of the GFS and ECMWF are in reasonable large-scale
   agreement Day 4 (Friday Aug. 21), this consistency begins to
   steadily diminish with time -- first at smaller scales, and then
   spilling over into the larger-scale flow field.  While a general
   trend toward flatter/more zonal flow through the period is evident,
   differences are great enough -- particularly with respect to the
   weakening/departure of eastern U.S. troughing -- so as to preclude
   any reasonable attempt at highlighting severe-weather risk areas at
   this time.

   ..Goss.. 08/18/2020

   CLICK TO GET WUUS48 PTSD48 PRODUCT
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