(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 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 040926
SPC AC 040926
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0326 AM CST FRI JAN 04 2013
VALID 071200Z - 121200Z
...DISCUSSION...
LATEST MEDIUM RANGE GUIDANCE SUGGEST SIGNIFICANT TROUGHING WILL
OCCUR ACROSS THE WRN U.S. EARLY NEXT WEEK. THERE IS CONSIDERABLY
DISCREPANCY BETWEEN THE ECMWF AND GFS REGARDING THE POSSIBILITY OF A
CLOSED LOW DIGGING INTO NRN MEXICO...ECMWF...OR A MORE PROGRESSIVE
LONG WAVE TROUGH EJECTING ACROSS THE CNTRL/SRN ROCKIES INTO THE SRN
HIGH PLAINS TUESDAY...GFS. IF THE MORE PROGRESSIVE NRN SOLUTION
OCCURS THERE IS SOME POSSIBILITY THAT A NARROW AXIS OF
MOISTURE/INSTABILITY COULD RETURN ACROSS THE LOWER MS VALLEY FOR
POTENTIAL THUNDERSTORM DEVELOPMENT. AT THIS TIME THERE IS TOO MUCH
UNCERTAINTY REGARDING THE EVOLUTION OF THIS FEATURE TO ACCURATELY
PREDICT CONVECTION...MUCH LESS ORGANIZED SEVERE.
..DARROW.. 01/04/2013
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