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Day 4-8 Severe Weather Outlook Issued on Aug 31, 2012
Updated: Fri Aug 31 08:55:03 UTC 2012
Day 4-8 Severe Weather Outlook Graphics Issued on Aug 31, 2012
D4Mon, Sep 03, 2012 - Tue, Sep 04, 2012 D7Thu, Sep 06, 2012 - Fri, Sep 07, 2012
D5Tue, Sep 04, 2012 - Wed, Sep 05, 2012 D8Fri, Sep 07, 2012 - Sat, Sep 08, 2012
D6Wed, Sep 05, 2012 - Thu, Sep 06, 2012 (All days are valid from 12 UTC - 12 UTC)
Note: A severe weather area depicted in the Day 4-8 period indicates a 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 highly unlikely during the entire period (e.g. less than a 30% probability for a regional severe storm area across the CONUS through the entire Day 4-8 period).

 Forecast Discussion

   ZCZC SPCSWOD48 ALL
   ACUS48 KWNS 310854
   SPC AC 310854
   
   DAY 4-8 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0354 AM CDT FRI AUG 31 2012
   
   VALID 031200Z - 081200Z
   
   ...DISCUSSION...
   MINOR DIFFERENCES BETWEEN MEDIUM-RANGE MODEL SOLUTIONS ARE EVIDENT
   AT THE START OF THE PERIOD -- MAINLY WITH EVOLUTION OF UPPER
   TROUGHING OVER WRN AND CENTRAL CANADA...AND THE ASSOCIATED EFFECT ON
   CONVECTIVE POTENTIAL OVER THE N CENTRAL AND EVENTUALLY THE NERN
   CONUS.  THE GFS TENDS TO KEEP TWO SEPARATE UPPER LOW CENTERS...WHICH
   PROGRESS STEADILY EWD.  MEANWHILE...THE ECMWF WEAKENS THE ERN-MOST
   LOW...SOMEWHAT MERGING THE TWO INTO ONE STRONGER LOW.
   
   IN EITHER CASE HOWEVER...WHILE SOME SEVERE THREAT COULD BE POSSIBLE
   FROM THE CENTRAL U.S. EWD ACROSS THE GREAT LAKES/OH VALLEY REGION
   THROUGH DAYS 6-7 /SEPT 5-6/...WIDESPREAD/SUBSTANTIAL SEVERE
   POTENTIAL APPEARS UNLIKELY.
   
   ..GOSS.. 08/31/2012

   CLICK TO GET WUUS48 PTSD48 PRODUCT

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