Day 4-8 Severe Weather Outlook Issued on Aug 17, 2020
Updated: Mon Aug 17 08:13:03 UTC 2020
Day 4 Risk
Area (sq. mi.)
Area Pop.
Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Day 5 Risk
Area (sq. mi.)
Area Pop.
Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Day 6 Risk
Area (sq. mi.)
Area Pop.
Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Day 7 Risk
Area (sq. mi.)
Area Pop.
Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Day 8 Risk
Area (sq. mi.)
Area Pop.
Some Larger Population Centers in Risk Area
No Risk Areas Forecast
D4
Thu, Aug 20, 2020 - Fri, Aug 21, 2020
D7
Sun, Aug 23, 2020 - Mon, Aug 24, 2020
D5
Fri, Aug 21, 2020 - Sat, Aug 22, 2020
D8
Mon, Aug 24, 2020 - Tue, Aug 25, 2020
D6
Sat, Aug 22, 2020 - Sun, Aug 23, 2020
(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 15%, 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 unlikely (i.e., less than 15%) for the forecast day.
Forecast Discussion
ZCZC SPCSWOD48 ALL
ACUS48 KWNS 170811
SPC AC 170811
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0311 AM CDT Mon Aug 17 2020
Valid 201200Z - 251200Z
...DISCUSSION...
Medium-range models appear to be in reasonable large-scale
agreement, in maintaining a ridge over the western U.S. and
low-amplitude troughing over the East. However, differences exist
at smaller scales, particularly with the progression/timing of
smaller-scale features moving through the main/westerly jet expected
to reside over southern Canada and the northern U.S. through most,
if not all, of the period. Since these features would likely be
associated with areas of greater convective coverage/intensity, this
lack of model-to-model consistency regarding these features --
suggestive to limited predictability -- makes delineation of any
severe risk areas difficult to impossible at this time.
..Goss.. 08/17/2020
CLICK TO GET WUUS48 PTSD48 PRODUCT
weather.gov 
@NWSSPC
