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< Day 3 Outlook    
Day 4-8 Severe Weather Outlook Issued on Dec 20, 2014
Updated: Sat Dec 20 10:12:03 UTC 2014
D4-8 D4 D5 D6 D7 D8
 Population  Cities  CWAs  Interstates  Counties  ARTCC  FEMA Regions

D4Tue, Dec 23, 2014 - Wed, Dec 24, 2014 D7Fri, Dec 26, 2014 - Sat, Dec 27, 2014
D5Wed, Dec 24, 2014 - Thu, Dec 25, 2014 D8Sat, Dec 27, 2014 - Sun, Dec 28, 2014
D6Thu, Dec 25, 2014 - Fri, Dec 26, 2014 (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 201010
   SPC AC 201010

   DAY 4-8 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0410 AM CST SAT DEC 20 2014

   VALID 231200Z - 281200Z

   ...DISCUSSION...
   TUESDAY /DAY 4/...MODELS REMAIN IN GOOD AGREEMENT REGARDING
   EVOLUTION OF A HIGH-AMPLITUDE UPPER TROUGH THAT IS FORECAST TO
   ADVANCE THROUGH THE LOWER MS VALLEY INTO THE SERN STATES TUESDAY. 

   THOUGH SOME UNCERTAINTY REMAINS REGARDING OVERALL SEVERE THREAT ON
   DAY 4 /PRIMARILY DUE TO EARLY ONSET OF PRECIPITATION/ FEEL AT LEAST
   A 15% AREA APPEARS WARRANTED FROM THE LOWER MS VALLEY INTO THE GULF
   COASTAL REGION INTO A PORTION OF THE FL PENINSULA. RICHER LOW-LEVEL
   MOISTURE WITH LOW-MID 60S DEWPOINTS WILL ADVECT INLAND CONTRIBUTING
   TO MODERATE INSTABILITY OVER THE LOWER MS VALLEY WHERE STEEPER LAPSE
   RATES WILL EXIST. CAPE WILL REMAIN LIMITED FARTHER EAST ALONG THE
   GULF COASTAL STATES DUE TO EARLY ONSET OF PRECIPITATION. STRONG
   SHEAR ACCOMPANYING THE UPPER TROUGH WILL BE SUFFICIENT FOR SEVERE
   STORMS. STORMS SHOULD INCREASE ALONG AND AHEAD OF THE FRONT AS WELL
   AS ALONG THE GULF COASTAL REGION...A FEW OF WHICH COULD BE STRONG TO
   SEVERE DURING THE DAY. OVERNIGHT...THE SEVERE THREAT MAY INCREASE
   FARTHER EAST OVER THE FL PENINSULA AS MCS OVER THE GULF MOVES
   INLAND.

   WEDNESDAY /DAY 5/ SOME SEVERE POTENTIAL MAY LINGER INTO DAY 5 ALONG
   THE ERN CAROLINAS AND POSSIBLY INTO THE FL PENINSULA AS UPPER TROUGH
   TAKES ON A NEGATIVE TILT AND WIND FIELDS STRENGTHEN.
   HOWEVER...PREDICTABILITY IS LOW DUE TO UNCERTAINTY REGARDING IMPACT
   THAT WIDESPREAD EARLY PRECIPITATION MAY HAVE ON INSTABILITY OVER THE
   CAROLINAS. 

   DAY 6-8...OVERALL SEVERE POTENTIAL WILL REMAIN GENERALLY LOW EXCEPT
   POSSIBLY DAY 7.

   ..DIAL.. 12/20/2014

   CLICK TO GET WUUS48 PTSD48 PRODUCT


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: December 20, 2014
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