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< Day 3 Outlook    
Day 4-8 Severe Weather Outlook Issued on Jun 21, 2018
Updated: Thu Jun 21 08:27:03 UTC 2018
D4-8 D4 D5 D6 D7 D8
 Population  Cities  CWAs  Interstates  Counties  ARTCC  FEMA Regions

D4Sun, Jun 24, 2018 - Mon, Jun 25, 2018 D7Wed, Jun 27, 2018 - Thu, Jun 28, 2018
D5Mon, Jun 25, 2018 - Tue, Jun 26, 2018 D8Thu, Jun 28, 2018 - Fri, Jun 29, 2018
D6Tue, Jun 26, 2018 - Wed, Jun 27, 2018 (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

   ACUS48 KWNS 210825
   SPC AC 210825

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0325 AM CDT Thu Jun 21 2018

   Valid 241200Z - 291200Z

   Substantial low-level moisture will remain over the eastern half of
   the CONUS through the period, with generally weak flow aloft. One
   possible focus for severe weather will be a slow-moving shortwave
   trough that is forecast to affect the central and northern High
   Plains on Sun/D4, and progress eastward across the mid MO and upper
   MS Valleys through Tue/D6. Moisture and instability will spread
   northward across the Plains ahead of this feature, with only a weak
   surface trough and nocturnal warm advection to focus development. As
   such, MCSs will be the primary storm mode, with areas of damaging
   wind as well as heavy rain. At this time, predictability is low. One
   possible area for a future upgrade will be eastern CO into KS on
   Sun/D4, as the shortwave trough emerges into the Plains. However,
   models indicate the potential for ongoing rain/storms over the area
   Sunday morning which decreases predictability.

   ..Jewell.. 06/21/2018


To retrieve previous Day 4-8 convective outlooks, enter the date YYYYMMDD (e.g., 20050310 for March 10, 2005.)
Data available since March 8, 2005.
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Page last modified: June 21, 2018
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