655
FXUS63 KGRR 092341
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
641 PM EST Sun Nov 9 2025

.KEY MESSAGES...

- Lake Effect Snow through Tonight

- Another Round of Lake Effect Snow Monday into Monday Night

- Warming Up through the Week

&&

.DISCUSSION...
Issued at 255 PM EST Sun Nov 9 2025

- Lake Effect Snow through Tonight

There are two areas of focus for lake effect snow through late
tonight. The first area between 131 and 127 where Lake Huron is
continuing snow showers across the area. Surface temperatures are
around freezing which is allowing snow to largely melt on roads.
However as the sun sets and temperatures fall we should see snow
stick to more surfaces. The focus for higher accumulations are in
Gratiot and Clinton counties where 2 to 4 isolated 5 inches of
snow is possible (40 to 60 percent). Further west and south a half
to 1 inch of snow before snow tapers off around 10PM. There is a
potential for the lake effect to continue later and any shift in
the main area of snow could result in adjustments to the current
Advisory.

The other area we are monitoring is the band of snow over Lake
Michigan that has started to impact Mason and Oceana counties.
Bursts of snow and gusty winds are expected through the afternoon
with around 1 to 3 inches of snow falling. This is expected to
taper off this evening. The southern extend of this band moving
into Berrien County will continue to shift east impacting potions
of Van Buren and southwest Allegan County. The orientation on the
lake along with support from the upper level low and lake
temperature/850 mb temperature differences around 20-25 C will
support moderate to heavy accumulations in far southwest Michigan
while the band remains overhead. 2 to 5 inches of snow is expected
across this area with isolated higher amounts possible (30
percent). The band is expected to shift back to the west late
tonight ending around midnight. Strong winds are also expected with
this band as it moves in, current winds speeds of 40 to 45 mph
have been observed.

Temperatures will be falling tonight into the 20s which brings
additional concerns for refreeze and icy conditions on untreated
surfaces. Make sure to drive slow in the snow through tonight and
use caution for the Monday morning commute.

- Another Round of Lake Effect Snow Monday into Monday Night

As the trough axis begins to shift east of the lake tomorrow,
northwest flow will take over and push the ongoing lake effect
band onshore and inland. This is expected to start in Mason and
Oceana counties for the morning rush hour and expand east with
snowfall largely along and west of 131. Another shortwave trough
will aid in bringing snow further inland across the area during
the late afternoon and evening hours, however the main focus for
accumulations will be along the lakeshore. The 25th to 75th
percentile put a swath of 2 to 6 inch snowfall amounts west of
131 with isolated higher amounts possible toward Ludington and
then the I-94 corridor. The HREF shows probabilities of snowfall
rates of 1 inch per hour in the 30 to 50 percent range during the
afternoon and evening. With these rates snow will quickly
accumulate on roads and visibilities drop creating hazardous
travel conditions. Another Advisory will likely be needed.

- Warming Up through the Week

Lake effect snow gradually tapers off Tuesday morning as 850mb
temperatures warm, however a push of warm air advection along with
convergence with the low level jet may spark off some light
rain/snow showers during the day. Another trough will move through
mainly to the north which could linger these rain/snow showers
toward the US-10 corridor into Wednesday. The warming trend
continues with highs in the low to mid 40s starting Wednesday into
the 50s by Saturday with dry conditions across the area.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 641 PM EST Sun Nov 9 2025

Light snow/snow showers continue at issuance time across all of
the terminals. There is somewhat of a boost coming from Saginaw
Bay with the winds from the NNE. We expect that the next few hours
will see some occasional IFR before the heavier snow showers
diminish. The light snow should then end from North to South
overnight, bringing likely VFR conditions to all sites.

Winds will become more from the NW by Monday afternoon. This will
bring lake effect snow showers off of Lake Michigan. KMKG and KAZO
are likely to see IFR in the heaviest snow showers. The impact
will taper off as you head east, with KLAN and KJXN likely to not
even see any lowering of conditions or snow showers.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Winter Weather Advisory until 7 PM EST this evening for MIZ037-
     043.
     Winter Weather Advisory until 10 PM EST this evening for MIZ052-
     059.
     Winter Weather Advisory until 1 AM EST Monday for MIZ071.
MARINE...Small Craft Advisory until 1 PM EST Tuesday for LMZ844>849.

&&

$$

DISCUSSION...RAH
AVIATION...NJJ