Day 4-8 Severe Weather Outlook Issued on Apr 25, 2021
Updated: Sun Apr 25 08:53:03 UTC 2021
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
Wed, Apr 28, 2021 - Thu, Apr 29, 2021
D7
Sat, May 01, 2021 - Sun, May 02, 2021
D5
Thu, Apr 29, 2021 - Fri, Apr 30, 2021
D8
Sun, May 02, 2021 - Mon, May 03, 2021
D6
Fri, Apr 30, 2021 - Sat, May 01, 2021
(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 250851
SPC AC 250851
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0351 AM CDT Sun Apr 25 2021
Valid 281200Z - 031200Z
...DISCUSSION...
A positively titled, southern-stream upper trough is forecast to
gradually move eastward across the Southwest on D4/Wednesday and
southern High Plains/southern Plains on D5/Thursday. Some severe
potential may exists across the southern Plains on D4/Wednesday as
this upper trough interacts with a moist antecedent air mass.
However, overall severe potential will depend largely on the
evolution of Tuesday night's thunderstorms and associated surface
boundaries. As such, predictability is limited at this forecast
range.
Guidance suggests the upper trough will gradually slow its forward
progress and trend towards an elongated upper low over northern
Mexico and Far West TX on D5/Thursday and D6/Friday. This evolution
would result in widespread cloudiness and precipitation, limiting
destabilization and resultant severe potential.
A shortwave trough is expected to move through the northern stream
from the Upper Midwest to the Lower Great Lakes/Mid OH Valley on
D4/Thursday and through the Northeast/northern Mid-Atlantic on
D5/Friday. Showers and thunderstorms are possible ahead of this
shortwave and its attendant cold front, but modest instability is
currently expected to preclude a widespread severe-thunderstorm
risk.
..Mosier.. 04/25/2021
CLICK TO GET WUUS48 PTSD48 PRODUCT
weather.gov 
@NWSSPC
