925
ACUS03 KWNS 230731
SWODY3
SPC AC 230730

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Sun Jun 23 2024

Valid 251200Z - 261200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF
IA/NORTHERN MO INTO NORTHERN IL...SOUTHERN WI...SOUTHWEST LOWER
MI...NORTHERN IN...FAR NORTHWEST OH...

...SUMMARY...
Severe thunderstorms are possible across parts of the Midwest and
Great Lakes on Tuesday.

...Parts of the Midwest/Great Lakes...
A Slight Risk has been introduced across parts of the Midwest and
Great Lakes, where confidence is currently highest in the
development of scattered strong to severe thunderstorms within a
moderately to strongly unstable environment. Uncertainty remains
rather high due to the potential influence of early-day convection.

A mid/upper-level shortwave trough and strong surface cyclone are
forecast to move across northern Ontario on Tuesday. A cold front
trailing from this cyclone is expected to move across parts of the
Great Lakes into the central Plains through the day and evening. A
strong belt of midlevel westerly flow will move across the upper
Great Lakes, with more modest flow farther south in the vicinity of
the front.

There is some potential for strong storms and possibly an MCS to
move across parts of WI/MI into northern IL/IN during the morning,
with at least an isolated severe threat. The position of the cold
front during the afternoon will likely be influenced to some extent
by early-day convection, though moderate low-level westerly flow
will support some recovery in the wake of morning outflow. The front
and any outflow boundaries are expected to become a focus for
scattered thunderstorm development during the afternoon and evening.

Rich low-level moisture beneath the eastward extension of the EML
will support moderate to strong buoyancy (MLCAPE of 1500-3000 J/kg)
along/ahead of the front. Effective shear will likely be relatively
modest (generally 25-35 kt), but sufficient for some storm
organization in combination with the strong buoyancy. A few stronger
cells/clusters will be possible initially, with a threat of hail,
strong/severe gusts, and possibly a tornado. Some upscale growth
will be possible, which could result in one or more corridors of
somewhat greater damaging-wind potential into the evening before the
threat begins to wane late in the period.

..Dean.. 06/23/2024

$$