442
ACUS48 KWNS 040909
SWOD48
SPC AC 040908

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0308 AM CST Tue Nov 04 2025

Valid 071200Z - 121200Z

...DISCUSSION...
...D4/Friday...
An area-of-interest, sufficient for a Predictability Too Low
highlight, appears centered on the OH Valley to Deep South. A
large-scale mid/upper trough should consist of several embedded
shortwave impulses progressing east from Hudson Bay through the
central to eastern CONUS. Primary surface cyclone is expected to
shift from the Upper Great Lakes into QC, with a trailing cold front
to its southwest undergoing frontolysis in the TN Valley/Deep South
by Friday night. Modified moisture return from the southern Gulf may
support moderate buoyancy over the Lower MS Valley, with a plume of
weak buoyancy extending into the OH/TN Valleys ahead of the front. A
belt of strong mid-level westerlies will yield favorable deep-layer
shear for organized severe potential. Latest GEFS-based SPC/NSSL ML
probs have trended upward with severe indications, more aggressive
than yesterday`s available NCAR ECENS-based guidance. Overall setup
may tend to favor a more mesoscale-driven 15% area given uncertainty
on timing of convective development along the southwest extent of
the weakening front and the degree of destabilization where ascent
is stronger to the northeast.

...D6/Sunday...
Substantial amplification of the next mid/upper trough is largely
progged across the central to eastern states late Saturday through
Sunday. This should induce more southerly cyclogenesis across the
North-Central States into the Lower Great Lakes. With the D4 wave
aiding in low-level moisture return from the southern Gulf, latest
guidance indicates seasonably rich dew points may be more prevalent
across the eastern Gulf and South Atlantic Coasts by late weekend.
This signal distinctly lacks run-to-run continuity, but should
foster at least low-probability severe potential across the
Southeast Coastal Plain.

..Grams.. 11/04/2025