Day 4-8 Severe Weather Outlook Issued on May 12, 2020
Updated: Tue May 12 08:58:02 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
Fri, May 15, 2020 - Sat, May 16, 2020
D7
Mon, May 18, 2020 - Tue, May 19, 2020
D5
Sat, May 16, 2020 - Sun, May 17, 2020
D8
Tue, May 19, 2020 - Wed, May 20, 2020
D6
Sun, May 17, 2020 - Mon, May 18, 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 120856
SPC AC 120856
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Tue May 12 2020
Valid 151200Z - 201200Z
...DISCUSSION...
A moist air mass is expected to be in place across the
central/southern Plains and mid/lower MS Valley on D4/Friday. A
slow-moving shortwave trough is forecast to move into the southern
Plains on D4/Friday, likely contributing to thunderstorm development
D4/Friday afternoon/evening into D5/Saturday morning from the TX
Hill Country northward in OK (possibly as far north as central KS).
Steep lapse rates and ample low-level moisture will result in a
strongly buoyant environment, but the weak flow aloft suggests a
somewhat limited potential for organized storms capable of severe
hazards.
Medium-range guidance is in good agreement that convective feedback
allows this shortwave trough to develop into a closed upper low on
D5/Saturday. This low is then forecast to become displaced from the
stronger westerlies and drift over the southern Plains toward the
Lower MS Valley into early next week.
Farther north, a shortwave trough is expected to move from the
northern Rockies across the northern/central Plains and into the
upper Midwest on D5/Saturday. Guidance differs on the development
and progression of the associated surface low, but some severe
threat may materialize near this low. The overall system is then
expected to continue eastward through the Northeast, where some
severe potential may also exist. Differences within the guidance
lead to low predictability and preclude introducing any areas yet.
..Mosier.. 05/12/2020
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