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< Day 3 Outlook    
Day 4-8 Severe Weather Outlook Issued on Dec 8, 2016
Updated: Thu Dec 8 10:02:02 UTC 2016
D4-8 D4 D5 D6 D7 D8
 Population  Cities  CWAs  Interstates  Counties  ARTCC  FEMA Regions

D4Sun, Dec 11, 2016 - Mon, Dec 12, 2016 D7Wed, Dec 14, 2016 - Thu, Dec 15, 2016
D5Mon, Dec 12, 2016 - Tue, Dec 13, 2016 D8Thu, Dec 15, 2016 - Fri, Dec 16, 2016
D6Tue, Dec 13, 2016 - Wed, Dec 14, 2016 (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 081000
   SPC AC 081000

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0400 AM CST Thu Dec 08 2016

   Valid 111200Z - 161200Z

   The 00Z GFS has trended closer to the ECMWF for day 4/Sunday with
   less amplification of a Pacific shortwave trough as it reaches the
   central Plains Sunday afternoon.  These models maintain a broad,
   cyclonic flow pattern across the contiguous U.S. until the start of
   day 5/Monday, and then diverge greatly in amplitude.  Although each
   shows cyclonic flow across the U.S., the GFS suggests much lower
   500-mb heights from the Rockies to the eastern states from day 5
   through day 7/Wednesday.

   Models suggest some strong to severe storm potential across the
   northwest Gulf Coast to the central Gulf Coast states during day
   5/Monday and day 6/Tuesday.  However, given the uncertainty in both
   the amplification of the upper flow pattern for the early part of
   next week and overall destabilization, no severe-weather
   probabilities will be included.

   ..Peters.. 12/08/2016


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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