Subj : DAY2SVR: Marginal Risk
To   : All
From : Mike Powell
Date : Tue Sep 05 2023 06:58:00

ACUS02 KWNS 050556
SWODY2
SPC AC 050554

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1254 AM CDT Tue Sep 05 2023

Valid 061200Z - 071200Z

....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MID MISSISSIPPI VALLEY...LOWER OHIO VALLEY AND CENTRAL GREAT
LAKES...

....SUMMARY...
Thunderstorms associated with marginally severe winds will be
possible on Wednesday from parts of the mid Mississippi Valley
north-northeastward into parts of lower Michigan. A potential for
hail is also expected in parts of the mid Mississippi and lower Ohio
Valleys.

....Mid Mississippi Valley/Lower Ohio Valley/Central Great Lakes...
An upper-level trough will move eastward across the mid to upper
Mississippi Valley on Wednesday. An associated cold front will
advance eastward into the southwestern Great Lakes and lower Ohio
Valley. Surface dewpoints ahead of the front are forecast to be in
the upper 60s and lower 70s F. The moist airmass will contribute to
the development of moderate instability by afternoon. Isolated to
scattered thunderstorms appear likely to form near and ahead of the
front during the mid afternoon. Several small convective clusters or
line segments will be possible as cell coverage increases during the
late afternoon and early evening.

Near the axis of strongest instability, NAM forecast soundings in
the late afternoon in far western Kentucky have MLCAPE peaking near
4000 J/kg, with 0-6 km shear around 30 knots. Flow above 500 mb is
forecast to be relatively weak. This will likely keep the primary
mode multicellular. As low-level lapse rates become steep in the mid
afternoon, the stronger multicells could be accompanied with
marginally severe winds. Hail could also occur, mainly in the mid
Mississippi and lower Ohio Valleys where the strongest instability
is forecast.

Further north into the southern Great Lakes, moderate instability is
forecast to develop ahead the cold front by afternoon. As low-level
convergence increases along the front and near a surface low in
Lower Michigan, a few marginally severe gusts will be possible with
the stronger multicells. The isolated wind-damage threat will likely
be greatest along the leading edge of the faster-moving short line
segments.

...Broyles.. 09/05/2023

$$
--- SBBSecho 3.14-Linux
 * Origin: Ilink: CCO - capitolcityonline.net (454:1/105)

.