165
FXUS63 KGRR 062330
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
630 PM EST Thu Nov 6 2025

.KEY MESSAGES...

- Rain tonight/Friday morning

- Rain changing to snow Saturday night, accums possible

&&

.DISCUSSION...
Issued at 234 PM EST Thu Nov 6 2025

- Rain tonight/Friday morning

Low pressure is currently in eastern North Dakota and will move
east tonight. A strong 50 kt llj is progd to develop and bring
moisture northward as evidenced by strong h8-h7 moisture transport
vectors. The result will be rain developing around midnight
tonight. QPF has trended upward during the past couple of model
runs and we`re now expecting a third to half inch of rain before
it ends Friday morning; Friday afternoon looks generally dry. The
cooler air behind the front won`t really begin filtering into the
region until late Friday. Thus, highs Friday will be above normal
in the mid 50s.

- Rain changing to snow Saturday night, accums possible

Our first taste of winter will arrive Saturday night. A clipper
type system will move from the northern Rockies southeast to
northern Indiana by Saturday evening. This will spread synoptic
precipitation across the cwa. The precipitation will be augmented
by a strong trailing short wave that will help to carve out the
deep upper trough. Forecast soundings suggest initially the
p-type will be rain, but quickly transition to wet snow around
midnight. Models show this to be a fairly quick-hitting system in
which the duration of snowfall may only be 4-6 hours. Given the
initial p-type of rain, snowfall accumulations will be held down
somewhat as well as from the warm ground.

Models are not in good agreement with snow totals, but generally
show 1-2 inches north of I-96 and 1-3/2-4 inches south of I-96.
That`s probably a good starting point.

Impact wise...there`re are still a lot of leaves on the trees and
wet snow may bring down some branches and cause power outages. The
warm ground may help to mitigate travel issues Saturday night.
That could change by Sunday/Monday, though, as colder air flows
into the cwa. Highs Sunday and Monday will only be in the mid 30s.
While we expect lake effect show showers during this time, Cold
air Sunday morning and especially Monday morning (lows in the
teens) may make for some hazardous travel. The ground will still
be warm. Then add a little snow which will melt and then quickly
refreeze in the cold air and we could see some travel issues.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 630 PM EST Thu Nov 6 2025

VFR conditions will continue until after 07z when MVFR conditions
spread from west to east. A frontal passage and associated
rainfall will lead to MVFR ceilings and visibilities across the
terminals with ceilings falling to IFR for a few hours behind the
front at all terminals except MKG. Isolated thunderstorms are
possible within the showers, given a few hundred joules of
elevated instability, however confidence in thunder is too low to
preclude a TAF mention. Conditions will improve in the later
portions of the TAF period as drier air filters into the area. A
period of LLWS is also expected late this evening into early
Friday morning as 50 knot winds around 2kft set up across the
terminals. Winds will increase ahead of the front to 10-20 knots
gusting to 30 knots, with winds shifting to westerly behind the
front as gusty winds continue.

&&

.MARINE...
Issued at 234 PM EST Thu Nov 6 2025

The pressure gradient will begin to tighten and winds will
increase after 00z tonight as low pressure approaches. Wind
profiles point toward mixing into the 40 kt range tonight. Thus,
the gale warning will remain in effect through mid Friday morning.
We`ll likely need a small craft advisory after that.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Gale Warning from 10 PM this evening to 10 AM EST Friday for
     LMZ844>849.

&&

$$

DISCUSSION...04
AVIATION...Thomas
MARINE...04