(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).
ZCZC SPCSWOD48 ALL
ACUS48 KWNS 260951
SPC AC 260951
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0351 AM CST WED NOV 26 2014
VALID 291200Z - 041200Z
THE MEDIUM-RANGE MODELS BEGIN THE DAY 4 TO 8 PERIOD WITH A ZONAL
FLOW PATTERN IN PLACE ACROSS MOST OF THE CONUS. MID-LEVEL FLOW
BECOMES A BIT MORE WEST-SOUTHWESTERLY ON SATURDAY/DAY 4 AS A SFC
HIGH MOVES EWD INTO THE ATLANTIC. A COLD FRONT IS FORECAST TO
ADVANCE SEWD ACROSS THE CNTRL STATES ON SUNDAY/DAY 5 WITH MOISTURE
RETURN AHEAD OF THE FRONT ACROSS THE SRN PLAINS...LOWER MS VALLEY
AND ARKLATEX REGIONS. ISOLATED THUNDERSTORM DEVELOPMENT COULD OCCUR
ALONG THE FRONT SUNDAY NIGHT IN THE LOWER TO MID MS VALLEY BUT
INSTABILITY SHOULD REMAIN QUITE WEAK. THE POTENTIAL FOR THUNDERSTORM
DEVELOPMENT MAY CONTINUE INTO MONDAY/DAY 6 ALONG THE MOIST CORRIDOR
IN THE LOWER MS VALLEY BUT THE ECMWF AND GFS SOLUTIONS DIFFER ON THE
UPPER-LEVEL PATTERN AND POSITION OF THE MOIST CORRIDOR WITH THE
ECMWF FURTHER TO THE EAST. BOTH MODELS KEEP LOW-LEVEL MOISTURE IN
PLACE ACROSS THE GULF COAST STATES ON TUESDAY/DAY 7 BUT LARGE
DIFFERENCES EXIST IN THE FORECAST UPPER-LEVEL PATTERNS. THIS
INTRODUCES CONSIDERABLE UNCERTAINTY AS TO THE POTENTIAL FOR
THUNDERSTORM ACTIVITY EARLY NEXT WEEK. ALTHOUGH INSTABILITY SHOULD
REMAIN WEAK ACROSS THE SRN STATES MONDAY AND TUESDAY...A LOCALLY
ENHANCED SEVERE THREAT CAN NOT BE TOTALLY RULED OUT.
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