537
FXUS63 KGRR 231136
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
636 AM EST Sun Nov 23 2025

.KEY MESSAGES...

- Rain Moving in Monday Night

- Cold with Snow Showers Wednesday and Thursday

- Snow/Mix end of the week

&&

.DISCUSSION...
Issued at 300 AM EST Sun Nov 23 2025

- Rain Moving in Monday Night

A southern stream upper low ejecting out of the Southwest U.S.
brings cyclogenesis across the Plains on Monday. The surface low
tracks into Lower Michigan with rain arriving Monday night into
Tuesday. This is quickly followed by a northern stream shortwave
trough amplifying into a closed upper low and full latitude
troughing by Wednesday,

- Cold with Snow Showers Wednesday and Thursday

Colder air wraps in behind the low with 850mb temps falling below
minus 10C on Wednesday into Thanksgiving. Broad cyclonic flow
along with inversion heights near 8 kft will allow snow showers to
develop and these should penetrate far inland given the west-
northwest flow and mean boundary layer winds near 40 mph. Snow
showers should diminish by Friday as heights rise with the upper
trough shifting east. Snow amounts uncertain at this range but it
should be cold enough for snow to accumulate on roads and affect
travel from Wednesday to Thursday night.

- Snow/Mix end of the week

A longwave trough amplifying across the western CONUS phases with
an upper low across Hudson Bay creating a large baroclinic zone
across the central U.S. with an active storm track bringing rounds
of wintry precip to the Great Lakes beginning late in the week.
This could cause travel impacts during the busy travel period next
weekend.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 634 AM EST Sun Nov 23 2025

VFR conditions will prevail through Monday morning. West winds
will gust to 20 knots at times today.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory until 1 PM EST this afternoon for
     LMZ844>849.

&&

$$

DISCUSSION...Ostuno
AVIATION...Ostuno