Skip Navigation Links 
NOAA logo-Select to go to the NOAA homepage NOAA's National Weather Service   Select to go to the NWS homepage
Storm Prediction Center
navigation bar left  
  navigation bar end cap is the U.S. Government's official Web portal to all Federal, state and local government Web resources and services.

< Day 3 Outlook    
Day 4-8 Severe Weather Outlook Issued on Feb 23, 2017
Updated: Thu Feb 23 09:38:03 UTC 2017
D4-8 D4 D5 D6 D7 D8
 Population  Cities  CWAs  Interstates  Counties  ARTCC  FEMA Regions

D4Sun, Feb 26, 2017 - Mon, Feb 27, 2017 D7Wed, Mar 01, 2017 - Thu, Mar 02, 2017
D5Mon, Feb 27, 2017 - Tue, Feb 28, 2017 D8Thu, Mar 02, 2017 - Fri, Mar 03, 2017
D6Tue, Feb 28, 2017 - Wed, Mar 01, 2017 (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 230936
   SPC AC 230936

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0336 AM CST Thu Feb 23 2017

   Valid 261200Z - 031200Z

   Significant model variability is evident amongst medium-range
   deterministic and ensemble data for the Sunday-Thursday (Day 4-8)
   period.  Both the GFS/ECMWF and MREF indicate the early stages of a
   return-flow pattern from the Gulf of Mexico into the southern Great
   Plains on Sunday (Day 4) and show a shortwave trough moving into the
   southern High Plains late Sunday.  The UKMET/CMC differ drastically
   on the depiction of the mid-level impulse.  On Monday (Day 5), the
   recent GFS and MREF model solutions differ substantially from the
   ECMWF in the placement of low-level boundaries across the
   south-central states and MS Valley.  The deterministic models and
   their ensembles generally show the eastward progression of a
   larger-scale mid-level trough from the western U.S. on Monday to the
   central-southern Rockies on Tuesday.  However, large differences are
   noted in relevant low-level mass fields --effectively resulting in
   large uncertainty and a predictability-too-low highlight for the
   entire Day 4-8 period.

   ..Smith.. 02/23/2017


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.
Weather Topics:
Watches, Mesoscale Discussions, Outlooks, Fire Weather, All Products, Contact Us

NOAA / National Weather Service
National Centers for Environmental Prediction
Storm Prediction Center
120 David L. Boren Blvd.
Norman, OK 73072 U.S.A.
Page last modified: February 23, 2017
Information Quality
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities