645
ACUS03 KWNS 021928
SWODY3
SPC AC 021928

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0228 PM CDT Tue Sep 02 2025

Valid 041200Z - 051200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THURSDAY IN A
CORRIDOR FROM THE LEE OF THE ALLEGHENY MOUNTAINS INTO THE TENNESSEE
VALLEY...

...SUMMARY...
Scattered strong thunderstorms may impact a corridor from the lee of
the Allegheny Mountains into the Tennessee Valley on Thursday,
accompanied by a risk for potentially damaging wind gusts.

...Discussion...
Models suggest that amplified large-scale mid-level troughing to the
east of the Canadian/U.S. Rockies may continue to gradually
consolidate during this period, becoming centered around a notable
deepening and occluding cyclone across northern Ontario, to the west
of James Bay.  Around the southwestern periphery of this feature, a
significant trailing short wave perturbation is forecast to dig
across the northern U.S. Great Plains and Midwest through lower
Great Lakes region, accompanied by a secondary surface cyclone and
reinforcing cold intrusion from the lee of the northern Rockies
through much of the central Great Plains and lower Missouri Valley
by daybreak Friday.  It appears that the occluding preceding front
will progress east/southeast of the lower Great Lakes and Ohio
Valley, before stalling and weakening, while seasonably high
moisture content remains confined to a remnant preceding boundary
across the southwestern Atlantic into southern Florida/southeastern
Gulf Basin.

...Northern Mid Atlantic into Tennessee Valley...
Aided by modestly steepening lower tropospheric lapse rates, it
appears that residual boundary-layer moisture may become supportive
of weak to modest destabilization, within at least a narrow
pre-frontal corridor across the region during the day Thursday.
This may include CAPE on the order of 500-1000 J/kg, in the presence
of strengthening, but still modest, cyclonic west-southwesterly
lower/mid-tropospheric flow, including 20-40+ kt in the 850-500 mb
layer.  It is possible that this environment may become conducive to
at least widely scattered strong thunderstorm development capable of
producing a few strong to potentially damaging wind gusts.

..Kerr.. 09/02/2025

$$