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< Day 3 Outlook    
Day 4-8 Severe Weather Outlook Issued on Mar 21, 2018
Updated: Wed Mar 21 07:41:03 UTC 2018
D4-8 D4 D5 D6 D7 D8
 Population  Cities  CWAs  Interstates  Counties  ARTCC  FEMA Regions

D4Sat, Mar 24, 2018 - Sun, Mar 25, 2018 D7Tue, Mar 27, 2018 - Wed, Mar 28, 2018
D5Sun, Mar 25, 2018 - Mon, Mar 26, 2018 D8Wed, Mar 28, 2018 - Thu, Mar 29, 2018
D6Mon, Mar 26, 2018 - Tue, Mar 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 210739
   SPC AC 210739

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0239 AM CDT Wed Mar 21 2018

   Valid 241200Z - 291200Z

   Models have come into much better agreement for the D4-D8 period,
   depicting an upper trough amplifying across the West and slowly
   progressing across the southern Plains.

   On Sunday/D5, a warm front will lift north across OK and into KS as
   low pressure forms over the central High Plains. Indications are
   that a leading shortwave trough will move across TX and OK
   relatively early in the day, which may induce midday storm formation
   in a warm advection regime from central OK into southwest MO. Thus,
   while a dryline will exist across southwest KS into western OK,
   additional diurnal development is uncertain. Conditionally, a few
   severe storms cannot be ruled out given potentially 1000-1500 J/kg
   MUCAPE beneath 40-50 kt southwesterly midlevel flow.

   For Monday/D6, the upper flow across the Plains will become a bit
   more meridional as the trough digs southward into northern Mexico. A
   strengthening speed max aloft will emerge across the southern high
   Plains late on Monday, with winds aloft roughly parallel to the
   dryline which itself will be quasi-stationary. Areas of storms are
   likely across much of west-central TX and OK, and a few could be
   strong or severe with wind or hail. Instability looks to be marginal
   for severe weather, but will also depend on how much early day
   convection there is. Thus, will maintain a predictability too low
   for Monday.

   The same pattern will persist into Tuesday/D7, shifting east OK and
   TX. By this time, heavy rain may become a concern, along with
   isolated severe storms.

   ..Jewell.. 03/21/2018


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: March 21, 2018
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