MD 1887 CONCERNING SEVERE THUNDERSTORM WATCH 552… FOR EASTERN SD…SOUTHWEST MN…NORTHWEST IA
Mesoscale Discussion 1887
NWS Storm Prediction Center Norman OK
0724 PM CDT Sun Oct 23 2022
Areas affected...eastern SD...southwest MN...northwest IA
Concerning...Severe Thunderstorm Watch 552...
Valid 240024Z - 240130Z
The severe weather threat for Severe Thunderstorm Watch 552
continues.
SUMMARY...Isolated severe thunderstorms will remain possible through
the mid evening before storms weaken as instability wanes.
DISCUSSION...Surface analysis places a low near Huron, SD with a
cold front extending southward into northern NE. A warm frontal
zone is over the Upper Midwest moving north and a narrow moist
sector extends from eastern NE into the eastern Dakotas and western
MN. Strong large-scale ascent continues to overspread the eastern
SD/southwest MN/northwest IA vicinity with strong low-level warm air
advection implied with a strong, veering wind profile (reference 00z
Omaha raob and KFSD VAD). The 00z Omaha raob showed weak buoyancy
(600 J/kg MUCAPE). With little low-level moisture advection
expected this evening, the cooling of the near-surface layer will
lessen buoyancy and likely lead to a weakening in storms by mid-late
evening as temperatures cool into the lower 70s over northwest IA
and remain in the lower 70s over west-central MN. However, a
short-term risk for isolated large hail and a strong to locally
severe gust may continue for the next 1-2 hours before diminishing.
..Smith.. 10/24/2022
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MPX...FSD...ABR...
LAT...LON 44769741 45009674 44509574 43539543 42849614 43029662
44769741
