FXUS63 KGRR 111748

Area Forecast Discussion
National Weather Service Grand Rapids MI
1248 PM EST Mon Dec 11 2023


Issued at 1141 AM EST Mon Dec 11 2023

No big changes to the going forecast for this afternoon. Surface
ridging is sliding east through the area today...so we are not
expecting much in the way of sensible weather. A westerly flow off
of Lake Michigan will keep the clouds locked in for most areas
through sunset. The exception may be the far south towards South
Haven and Kalamazoo where a backing wind to the west-southwest may
take the lake out of play and open up some clearing there late in
the day. Overall though, benign weather with gray skies and
temperatures in the 30s.


.SHORT TERM...(Today through Tuesday)
Issued at 312 AM EST Mon Dec 11 2023

We have been monitoring observations across the area and outside our
door this morning for any evidence that freezing drizzle is "heavy"
enough to cause impacts and require the need for messaging about it.

All of the area observations have not shown any kind of restriction
to visibility since the snow showers moved through just before
midnight. Outside the door here, there is the slightest hint of some
very light mist, but it is not freezing on any sfcs so far. The T/Td
depression is likely enough to help it evaporate before freezing on

The good news is that the very light radar echoes are shrinking in
coverage and intensity, and with that the chance for any meaningful
frozen pcpn. This is occurring as the upper trough is shifting east
of the area, and the cyclonic flow aloft is transitioning to anti-
cyclonic flow.

The low level flow will back a bit today eventually to become from
the SW. There may be a couple of residual lake effect flurries/light
snow showers as the flow becomes more onshore. Forecast soundings
indicate a thin layer of the dgz barely being saturated, leading to
the light drizzle/freezing drizzle/snow threshold being very close.

It does look like any snow showers will end by this evening.
Indications are that the low clouds will gradually move/erode from
SW to NE this evening as lake effect ends as temps aloft warm
sufficiently. We will see a weak front try and clip the northern
portion of the area late tonight and early Tuesday. This will help
low clouds to try to redevelop, and to bring a small chc of pcpn to
the U.S.-10 corridor.

That should move out Tuesday morning, and allow skies to try to
clear out once again no later than Tuesday evening.

.LONG TERM...(Tuesday night through Sunday)
Issued at 312 AM EST Mon Dec 11 2023

No significant weather expected through next weekend. A trough axis
moves east on Wednesday with shortwave ridging for Thursday. Mostly
clear skies are expected for the peak of the Geminid meteor shower
on Wednesday night.

Only slight chance POPs in the forecast for Friday with a weak
trough and sfc cold front slowly settling south across the Great
Lakes. A weak clipper could moves along the front over the weekend.
Forecast soundings show little moisture to work with and the mean
path of the sfc low remains north of the forecast area, so little if
any QPF is expected.


.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1248 PM EST Mon Dec 11 2023

A solid MVFR cloud deck remains in place over lower Michigan, but
clouds will scour out into VFR late tonight into Tuesday morning.
Winds will shift more southwesterly through the night, then will
turn westerly after 12z Tuesday. Increasing winds are expected
this evening through the overnight to around 15 knots with gusts
to 20 to 25 knots.


Issued at 312 AM EST Mon Dec 11 2023

We are hoisting a Gale Warning for Pentwater to Manistee for
tonight, and hoisting a Small Craft Advisory for the rest of the
area from this evening through Wednesday.

We are in a relative lull this morning with regards to winds and
waves. The gusty winds over the last couple of days have moved out.
This will be short lived as the gradient will pick up out of the SW
ahead of a system that will moving by to our north. Winds will
diminish a bit after tonight, but will stay up enough until early
Wednesday to keep the SCA in effect. Waves do not come down enough
until late Wednesday.


LM...Small Craft Advisory from 10 PM this evening to 7 PM EST
     Wednesday for LMZ844>848.

     Gale Warning from 10 PM this evening to 7 AM EST Tuesday for



LONG TERM...Ostuno