(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 230846
SPC AC 230846
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0346 AM CDT WED JUL 23 2014
VALID 261200Z - 311200Z
HIGH CONFIDENCE EXISTS IN THE TRANSITION TO AN AMPLIFIED UPPER-LEVEL
PATTERN CONSISTING OF A TROUGH IN THE EAST AND RIDGE IN THE WEST. A
SUBSTANTIAL MID-LEVEL VORTICITY MAX OVER THE SRN CANADIAN PRAIRIES
AT 12Z/SAT SHOULD DAMPEN SOMEWHAT AS IT TRACKS TOWARDS THE GREAT
LAKES THIS WEEKEND. A BELT OF STRONG MID-LEVEL W/NWLYS WILL
ACCOMPANY THIS IMPULSE...LIKELY OVERLAPPING PARTS OF A WARM/MOIST
SECTOR THAT WILL BE SHUNTED S BY A PROGRESSIVE COLD FRONT. AT LEAST
MINIMAL SEVERE PROBABILITIES ARE APPARENT D4-5 ACROSS THE MIDWEST TO
MID-MS/TN VALLEYS WHERE INSTABILITY MAY BE ROBUST WITHIN AN EML
PLUME. BUT MESOSCALE PREDICTABILITY IN THIS TIME FRAME REMAINS TOO
LOW TO RELIABLY DELINEATE A 30 PERCENT OR GREATER AREA.
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