(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 240923
SPC AC 240923
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0323 AM CST MON NOV 24 2014
VALID 271200Z - 021200Z
THE MEDIUM RANGE MODELS BEGIN THE DAY 4 TO 8 PERIOD WITH AN
UPPER-LEVEL TROUGH ALONG THE EAST COAST AND MOVE THIS FEATURE SLOWLY
EWD ON THURSDAY/DAY 4 WITH THE TROUGH MOVING OFFSHORE BY THURSDAY
NIGHT. AT THE SFC...HIGH PRESSURE IS FORECAST TO DOMINATE THE CNTRL
AND ERN STATES ON THURSDAY WITH THE HIGH MOVING TO THE EAST COAST BY
FRIDAY/DAY 5. AT THIS TIME...THE MODELS ARE FORECASTING WEST TO
NORTHWEST MID-LEVEL FLOW TO BE ESTABLISHED ACROSS MUCH OF THE CONUS.
THE SFC HIGH SHOULD KEEP DRY AIR IN PLACE OVER MOST OF THE NATION
UNTIL FRIDAY NIGHT WHEN RETURN FLOW IS FORECAST TO DEVELOP ACROSS
THE SRN PLAINS. AS A RESULT...A CORRIDOR OF LOW-LEVEL MOISTURE MAY
SETUP FROM THE SRN PLAINS EWD INTO THE LOWER MS VALLEY ON
SATURDAY/DAY 6. THUNDERSTORM ACTIVITY WILL BE POSSIBLE ALONG THE
MOIST AXIS FROM SATURDAY AFTERNOON INTO SUNDAY AHEAD OF A COLD FRONT
THAT IS FORECAST TO BE IN THE SRN PLAINS. AT THIS POINT...AN
ENHANCED SEVERE THREAT ON SATURDAY OR SUNDAY/DAY 7 APPEARS UNLIKELY
BECAUSE OF WEAK INSTABILITY. HOWEVER...DUE TO THE FORECAST RANGE...A
SEVERE WEATHER SCENARIO CAN NOT BE TOTALLY RULED OUT.
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