590
ACUS02 KWNS 100502
SWODY2
SPC AC 100501

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1101 PM CST Tue Dec 09 2025

Valid 111200Z - 121200Z

...NO THUNDERSTORM AREAS FORECAST...

...SUMMARY...
The risk for thunderstorms appears negligible across the U.S.
Thursday through Thursday night.

...Discussion...
Downstream of an increasingly prominent blocking high building near
and to the north of the Aleutians, mid-level developments across the
eastern Pacific into western North America are still forecast to
include a belt of strong flow veering to an increasing northwesterly
component across British Columbia and adjacent portions of the
Pacific Northwest, through portions of the Canadian Prairies and
northern U.S. Great Plains during this period.  One or two short
wave perturbations on the leading edge of this regime will begin to
reinforce broad downstream troughing across the Mississippi Valley
into western Atlantic.

Mid-level flow is likely to remain cyclonic as far south as the Gulf
Coast states, but heights across much of the South may tend to rise
in the wake of a significant lower/mid-tropospheric cyclone forecast
to migrate out of the Northeast through the Canadian Maritimes.
While progressing farther offshore to the north, it still appears
that the primary trailing frontal zone may stall/retreat
northeastward across the southern Atlantic Coast through Tennessee
Valley vicinity, while advancing southward through the lower
Missouri Valley and central Great Plains vicinity by late Thursday
night.  At the same time, much colder air probably will continue to
gradually nose southward to the lee of the Canadian and northern
U.S. Rockies.

Models indicate that a remnant preceding front will become more
diffuse across the central through northwestern Gulf Basin, and a
gradual boundary-layer modification may continue across the
northwestern Gulf as a weak southerly return flow begins to develop.
Some boundary-layer moistening appears possible inland across Texas
coastal areas, but forecast soundings indicate that this will occur
beneath pronounced warm/dry layers in the lower/mid-troposphere,
precluding appreciable destabilization through this period.

..Kerr.. 12/10/2025

$$