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Day 4-8 Severe Weather Outlook Issued on Oct 18, 2017
Updated: Wed Oct 18 06:58:02 UTC 2017
Day 4-8 Severe Weather Outlook Graphics Issued on Oct 18, 2017
Day 4 Severe Weather Outlook Graphics Issued on Oct 18, 2017
Day 4 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
15 % 93,314 11,390,140 Dallas, TX...Fort Worth, TX...Oklahoma City, OK...Tulsa, OK...Arlington, TX...
Day 5 Severe Weather Outlook Graphics Issued on Oct 18, 2017
Day 5 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Day 6 Severe Weather Outlook Graphics Issued on Oct 18, 2017
Day 6 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Day 7 Severe Weather Outlook Graphics Issued on Oct 18, 2017
Day 7 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Day 8 Severe Weather Outlook Graphics Issued on Oct 18, 2017
Day 8 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
D4Sat, Oct 21, 2017 - Sun, Oct 22, 2017 D7Tue, Oct 24, 2017 - Wed, Oct 25, 2017
D5Sun, Oct 22, 2017 - Mon, Oct 23, 2017 D8Wed, Oct 25, 2017 - Thu, Oct 26, 2017
D6Mon, Oct 23, 2017 - Tue, Oct 24, 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

   ZCZC SPCSWOD48 ALL
   ACUS48 KWNS 180656
   SPC AC 180656

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0156 AM CDT Wed Oct 18 2017

   Valid 211200Z - 261200Z

   ...DISCUSSION...
   Medium-range models are in general agreement regarding the evolution
   of a short-wave trough as it migrates across the western US late
   this week before affecting the Plains/MS Valley during the day4/5
   time period. While there remain timing differences among the models,
   with the ECMWF being the fastest, most agree that significant height
   falls will spread into the central Plains Saturday with lesser
   certainty across lower latitudes into the day5 period. Higher-PW air
   mass will advance northward across OK/KS prior to a strong frontal
   passage and adequate instability should be in place for robust
   convection along the surging boundary, including the possibility for
   severe. For these reasons have introduced 15% severe probs from
   eastern KS into north-central TX where greatest confidence in
   buoyancy overlaps expected thunderstorm development. Predictability
   decreases Sunday as models begin to diverge in their solutions.
   However, some threat for strong storms may evolve across the upper
   TX Coast into LA and this region will be monitored for possible
   inclusion of severe probs in later outlooks.

   ..Darrow.. 10/18/2017

   CLICK TO GET WUUS48 PTSD48 PRODUCT
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Page last modified: October 18, 2017
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