261
ACUS02 KWNS 190551
SWODY2
SPC AC 190549

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1249 AM CDT Thu Sep 19 2024

Valid 201200Z - 211200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN A PART OF THE
MIDWEST...

...SUMMARY...
Isolated, marginally severe thunderstorms are possible in the late
afternoon Friday in parts of Illinois, Indiana, and southwest Lower
Michigan.

...Midwest...
A low-amplitude shortwave trough will pass across the Upper to
Central Great Lakes during the first half of the period. This will
outpace a cold front that trails from a cyclone shifting northeast
in MB, yielding a largely weakening to stalling front by Friday
evening. Most guidance suggests at least isolated thunderstorms
should form within a low-level warm conveyor ahead of the front,
generally focused on a moderate buoyancy plume emanating northeast
from parts of MO/AR. A fast westerly upper jet will further impinge
on this portion of the front as well, favorably timed with peak
boundary-layer heating. A few marginally severe storms may develop
within this regime. Despite weak mid-level lapse rates, elongation
of the mid to upper hodograph should support a threat for 1-1.5 inch
hail, along with strong to marginally severe gusts from 45-60 mph.
These threats should diminish quickly after sunset.

...Southern High Plains...
Locally strong gusts are possible during the late afternoon to early
evening with high-based, low-topped convection amid a weak buoyancy
environment. The region will remain between a stout mid-level
anticyclone over the Lower Rio Grande Valley and a southern-stream
shortwave trough slowly moving across CA into AZ. Relatively warm
mid-level temperatures should preclude appreciable storm intensity,
but well-mixed boundary layers could support sporadic gusts
approaching severe levels.

...Central Great Plains...
Isolated elevated storms may develop overnight into Saturday morning
within a strengthening warm theta-e advection regime. Weak mid-level
lapse rates should temper elevated buoyancy and limit hail potential
to some extent. But sufficient mid to upper-level speed shear could
foster small hail production.

..Grams.. 09/19/2024

$$