(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 230834
SPC AC 230834
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0334 AM CDT SAT AUG 23 2014
VALID 261200Z - 311200Z
MODEL-TO-MODEL AGREEMENT AMONGST VARIOUS MEDIUM-RANGE PROGS
DETERIORATES STEADILY WITH TIME WITHIN THE LATEST MODEL RUNS...WITH
RESPECT TO DEPICTION OF THE SYNOPTIC-SCALE PATTERN ACROSS THE CONUS.
WHILE MOST RUNS KEEP A TROPICAL SYSTEM OFF THE SE U.S. COAST --
I.E. OVER THE GULF STREAM...THE UKMET DOES DEPICT LANDFALL ON OR
AROUND DAY 6 /THU 8-28/ ALONG THE CAROLINA COAST.
OTHERWISE...SUBSTANTIAL DISCREPANCY IS EVIDENT BETWEEN THE GFS AND
ECMWF WITH RESPECT TO EJECTION OF A WRN U.S. TROUGH INTO/ACROSS THE
CENTRAL CONUS. WHILE AT LEAST AN ISOLATED SEVERE RISK WOULD LIKELY
ACCOMPANY THE ADVANCE OF THIS SYSTEM...LARGE TIMING DIFFERENCES --
EVEN AS EARLY AS LATE DAY 4/EARLY DAY 5 -- RENDER ANY ATTEMPT AT
HIGHLIGHTING DAYS/LOCATIONS OF ANY SPECIFIC RISK IMPOSSIBLE ATTM.
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