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< Day 3 Outlook    
Day 4-8 Severe Weather Outlook Issued on Mar 27, 2023
Updated: Mon Mar 27 08:39:02 UTC 2023
D4-8 D4 D5 D6 D7 D8
 Pop.  Cities  CWAs  RFCs  Interstates  Counties  ARTCC  FEMA  Tribal

D4Thu, Mar 30, 2023 - Fri, Mar 31, 2023 D7Sun, Apr 02, 2023 - Mon, Apr 03, 2023
D5Fri, Mar 31, 2023 - Sat, Apr 01, 2023 D8Mon, Apr 03, 2023 - Tue, Apr 04, 2023
D6Sat, Apr 01, 2023 - Sun, Apr 02, 2023 (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 270836
   SPC AC 270836

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0336 AM CDT Mon Mar 27 2023

   Valid 301200Z - 041200Z

   An upper trough will shift east across the western U.S. to the
   central/southern Rockies on Day 4/Thu. Forecast guidance has come
   into better agreement with a slower eastward ejection of the trough.
   As such, the 15 percent severe area for Thursday has been shrunk
   compared to previous days. Some severe potential, albeit more
   conditional, will still exist as strong surface cyclogenesis occurs
   over the central High Plains. In response to this developing low,
   strengthening southern low-level flow across the southern/central
   Plains will transport upper 50s to mid 60s F dewpoints across
   TX/OK/KS to the east of a dryline. Large-scale ascent is expected to
   be modest as the main trough remains too far west. However, strong
   vertical shear will overlap a moderately unstable airmass. If
   thunderstorms can develop/overcome capping, isolated supercells
   capable of all hazards will be possible in the vicinity of the
   dryline from late afternoon into Thursday night.

   By Day 5/Fri, all-hazards severe potential will expand across a
   large portion of the central U.S. There is still some uncertainty in
   timing and intensity of the ejecting upper trough. Nevertheless, a
   broad warm sector is expected to develop from eastern portions of
   the southern Plains toward the Mid/Lower MS Valley through the
   afternoon, and eastward to the Lower OH/TN Valley vicinity by
   evening/overnight. Intense southwesterly mid/upper flow will overlap
   the warm sector as a cold front tracks east/southeast. The severe
   threat could end up taking a bi-modal character, with an area of
   enhanced potential focused near a strong surface low over the IA/IL
   vicinity, and another area focused further south toward the
   Mid-South where large-scale ascent will be weak, but a better
   thermodynamic environment will overlap with strong shear. However,
   enough differences exist in forecast guidance regarding the location
   of the surface low track and amplitude of the ejecting upper trough
   that a broad 15 and 30 percent severe delineation has been
   introduced. These areas will likely change some in the coming days
   as forecast details become better resolved.

   Severe potential could continue eastward toward the Mid-Atlantic and
   Southeast on Day 6/Saturday. A moist boundary-layer will exist
   across these areas ahead of the east/south advancing cold front.
   However, timing and location of the surface low and focus of strong
   shear/large-scale ascent is uncertain, and predictability is too low
   to delineate any areas at this time.

   Large spread in forecast guidance continues/increases during the end
   of the forecast period, and predictability remains low on Days

   ..Leitman.. 03/27/2023


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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