139
FXUS63 KGRR 011144
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
744 AM EDT Sat Nov 1 2025

.KEY MESSAGES...

- Some Showers Possible Mainly Near/South of I-96 Today

- A Few Showers Early Monday and Then Again Wednesday

- Additional Rain Possible Next Weekend

&&

.DISCUSSION...
Issued at 330 AM EDT Sat Nov 1 2025

- Some Showers Possible Mainly Near/South of I-96 Today

Lake effect rain showers have been ongoing this morning but the
activity has been light. Steadier showers through the morning and
early afternoon hours will likely be confined to near and south
of I-96 and especially across Ottawa and Allegan counties where
HREF LPMM 24 hr QPF is showing 0.25"-0.50" or a bit more possible.
Can`t totally rule out a rumble of thunder with lake induced
MUCAPE values of 100-150 J/kg right along the immediate lakeshore.
Elsewhere, periodic showers are possible with light amounts
expected. This activity may continue into the afternoon hours
before diminishing.

- A Few Showers Early Monday and Then Again Wednesday

Monday will feature some early morning showers as an upper
shortwave trough and trailing surface cold front clips central and
northern Lower MI. Highest POPs are featured north of I-96, but
many areas should see some early morning showers Monday before
rapidly moving out of the region. Breezy conditions Monday are
likely with wind gusts around 30 mph possible.

For Wednesday, another upper shortwave passes through the Great
Lakes with a quick hitting, weak surface low forecast to impact
the state. Again, some morning showers look possible and breezy
conditions during the day similar to Monday could occur.

- Additional Rain Possible Next Weekend

Ensemble and deterministic model guidance favor an active pattern
Friday into the weekend with steadier rain possible, including a
risk for some thunderstorms and gusty synoptic scale winds. ECE
and CMC ensemble mean 500 mb heights/vorticity favor a seasonably
deep upper trough moving through during this timeframe with
surface cyclogenesis possible over the Great Lakes. Depending on
strength, location, and timing of this potential system, a more
widespread rainfall could occur and some MUCAPE is hinted at from
ECE members so not out of the question some thunderstorms could
occur.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 739 AM EDT Sat Nov 1 2025

Spotty lake effect showers continue this morning. Isolated shallow
ground fog has developed at times during breaks in cloud cover,
but that will be ending soon after sunrise. VFR or MVFR is
expected within the showers. Most likely locations to get rain
would be MKG and GRR, though a shower could pop up near or over
any given terminal. Impacts should be minimal, however.

&&

.MARINE...
Issued at 330 AM EDT Sat Nov 1 2025

Gale Watch is being issued from Pentwater to the north for
potential gales Sunday evening into Monday as SW winds strengthen
over the lake ahead of the next system to move through the region.
Wave action could exceed 10 feet into Monday for portions of our
nearshore waters.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Gale Watch from Sunday afternoon through Monday morning for
     LMZ849.

&&

$$

DISCUSSION...Hoving
AVIATION...Hoving
MARINE...Hoving