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< Day 3 Outlook    
Day 4-8 Severe Weather Outlook Issued on Jan 27, 2021
Updated: Wed Jan 27 09:44:03 UTC 2021
D4-8 D4 D5 D6 D7 D8
 Pop.  Cities  CWAs  RFCs  Interstates  Counties  ARTCC  FEMA  Tribal

D4Sat, Jan 30, 2021 - Sun, Jan 31, 2021 D7Tue, Feb 02, 2021 - Wed, Feb 03, 2021
D5Sun, Jan 31, 2021 - Mon, Feb 01, 2021 D8Wed, Feb 03, 2021 - Thu, Feb 04, 2021
D6Mon, Feb 01, 2021 - Tue, Feb 02, 2021 (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 270941
   SPC AC 270941

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0341 AM CST Wed Jan 27 2021

   Valid 301200Z - 041200Z

   ...DISCUSSION...
   Medium-range models continue to exhibit reasonable large-scale
   agreement with respect to evolution of the upper pattern, through
   roughly Day 7.  Beyond that, differences quickly arise with handling
   of a large trough crossing the West late in the period.

   Prior to then, the pattern aloft will be characterized by the
   progression of a trough -- initially situated over the southern
   Rockies/central and southern High Plains.  As this feature
   evolves/shifts eastward with time, it will be accompanied by a
   well-developed surface low/frontal system, that models suggest will
   move from the High Plains early Day 4 (Saturday), to near/off the
   East Coast by the end of Day 6 (Tuesday morning).  

   Despite the well-developed nature of this surface system, its warm
   sector will likely remain notably lacking in instability, due to the
   antecedent cP airmass intrusion through the Gulf of Mexico, and 
   persistence of ridging aloft across the western Atlantic and into
   the Gulf.  As such, though precipitation -- including
   weak/low-topped convection -- will accompany passage of the system,
   severe weather is not expected.

   ..Goss.. 01/27/2021

   CLICK TO GET WUUS48 PTSD48 PRODUCT


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: January 27, 2021
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