170
ACUS01 KWNS 200046
SWODY1
SPC AC 200045

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0745 PM CDT Thu Sep 19 2024

Valid 200100Z - 201200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE
UPPER MISSISSIPPI VALLEY INTO PARTS OF NORTHEAST OKLAHOMA...

...SUMMARY...
Scattered strong to severe storms remain possible through this
evening from the upper Mississippi Valley southward into northeast
Oklahoma.

A shortwave trough will shift northeastward out over the Dakotas and
MN this evening, as an upper low moves northeastward across MB.
Winds aloft will weaken over the area, though cooling aloft will
continue spreading into the upper Great Lakes.

At the surface, a weak front/wind shift extends from the main
surface low over MB southward across MN and into IA, and from
southeast KS into northwest OK.

The strongest cells currently stretch from the MN Arrowhead
southward into north central IA, with primarily discrete storm mode
along the front. Farther south, a secondary area of storms persist
over southeast KS into northeast OK.

Tornado watch #678 continues over northwest WI this evening, where
low-level shear is a bit stronger. Storms across this area may
persist for several more hours before dissipating, as temperatures
aloft are cooling.

Farther south, Severe Thunderstorm watches #677 and #679 continue
along the boundary, where storms remain within the diurnal
instability axis. Temperatures aloft are quite warm here, and storms
should dissipate sooner than points north.  Until then, locally
severe gusts or hail will be possible.

For more information see mesoscale discussion #2089.

..Jewell.. 09/20/2024

$$