..DISCUSSION...
...Day 4/Wed...
A large-scale upper trough will continue to shift east across the
central U.S. on Wednesday, becoming oriented from the Upper Great
Lakes to the central Gulf coast vicinity by Thursday morning. An
embedded shortwave within the base of this trough will move from the
southern Plains to the Deep South, while the northern branch of the
trough moves across the Midwest. Strong deep-layer southwesterly
flow will overspread a broad warm sector across much of the Midwest
and southern U.S. Meanwhile, a cold front will develop southeast
through the period, tracking across much of the Mid/Lower MS, OH and
TN Valleys.
Uncertainty exists regarding where convection may be ongoing
Wednesday morning, and some potential exists for widespread
thunderstorm activity across parts of the Midwest. As a result, it
is uncertain how far north quality thermodynamics will exist.
Nevertheless, it appears likely at least some severe risk will exist
across the Ohio Valley given favorable boundary-layer moisture and
impressive vertical shear profiles. Further southwest toward the
Lower MS Valley into the Deep South vicinity, morning convection may
be more limited compared to further north, allowing for more
extensive destabilization ahead of the surging cold front. A
mixed-mode of supercells ahead of the cold front, and an organized
line of storms along the cold front will be possible across this
area.
As mesoscale details become better resolved in the coming days, the
severe area for Wednesday is likely to shift some. However, the
overall pattern suggests a broad area of severe thunderstorm
potential is probable on Wednesday.
...Leitman.. 03/08/2026
