511
ACUS02 KWNS 021704
SWODY2
SPC AC 021703

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1203 PM CDT Tue Sep 02 2025

Valid 031200Z - 041200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LATE WEDNESDAY
AFTERNOON INTO EVENING ACROSS PARTS OF CENTRAL AND EASTERN KANSAS
INTO WEST CENTRAL MISSOURI...

...SUMMARY...
Scattered strong thunderstorms will impact parts of the central
Great Plains into Missouri Ozarks late Wednesday afternoon and
evening, accompanied primarily by a risk for severe hail and
potential for damaging wind gusts.

...Discussion...
The large-scale mid/upper flow regime remains amplified across the
eastern mid-latitude Pacific through North America, with little
appreciable change forecast through this period.  Troughing will be
maintained east of the Canadian/U.S. Rockies, as far south as the
Gulf Basin into southwestern Atlantic, reinforced by a pair of
vigorous digging short wave perturbations emerging from the northern
mid- to Arctic latitudes of northwestern Canada.

The lead impulse is forecast to be in the process of digging across
the international border through portions of the northern U.S. Great
Plains and Upper Midwest by 12Z Wednesday.  Models indicate that
this will contribute to notable lower/mid-tropospheric cyclogenesis
near/north of Lake Superior, toward the James Bay vicinity, through
daybreak Thursday, as the trailing perturbation digs southeast of
the Northwest Territories through eastern Canadian Prairies.

While one initial weakening frontal zone (and associated plume of
seasonably high moisture content) lingers across the central Gulf
through southern Florida Peninsula/Straits vicinity, an initial
reinforcing intrusion of cooler/drier air is forecast to surge into
the Ohio Valley and through much of the central Great Plains by late
Wednesday night.  Another will begin nosing southward to the lee of
the Canadian toward northern U.S. Rockies.

...Central Great Plains into Missouri Ozarks...
Near the southwestern periphery of strengthening northwesterly
mid-level flow (including 40+ kt around 500 mb), models continue to
indicate that a plume of steepening lower/mid-tropospheric lapse
rates will advect across the central Great Plains toward adjacent
lower Missouri Valley vicinity during the day.  Beneath this regime,
it appears that residual boundary-layer moisture will remain
sufficient to support the development of moderate potential
instability, generally becoming focused in a corridor along/ahead of
the southward advancing front and pre-frontal surface troughing by
late afternoon.

Uncertainties do linger due to continuing spread in the model
output, particularly with regard to the degree of mid/upper forcing
for ascent overspreading the region during the peak late afternoon
instability, to the southwest of the primary digging mid-level
trough/evolving low near the upper Great Lakes.  With sufficient
lift to overcome mid-level inhibition, the sheared environment will
likely be conditionally conducive to organized severe convection.
It is possible that this could be limited to one or two supercells
and/or a small upscale growing cluster.  However, this activity
could become capable of producing large hail and potentially
damaging wind gusts for at least a few hours late Wednesday
afternoon into evening.

..Kerr.. 09/02/2025

$$