740
FXUS63 KMQT 042000
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
300 PM EST Thu Dec 4 2025

.KEY MESSAGES...

- Weak clipper systems will provided light snow chances this
  weekend with lake effect snow following for the NW wind
  snowbelts.

- Gale Warnings are in effect for much of Lake Superior for
  anticipated southwest gusts 35-40 kts tonight through Friday
  morning.

- Colder than normal temperatures continue through the forecast.
  Expect wind chills below zero across much of the U.P. tonight.

&&

.DISCUSSION...
Issued at 257 PM EST Thu Dec 4 2025

Early afternoon RAP analysis and GOES Satellite imagery reveals
clearing skies overhead da Yoop as lake effect clouds/snow are
starting to kick offshore with winds backing to the SW ahead of a
low amplitude clipper. Present satellite loop shows this SW backing
nearly complete in the west while lingering lake effect will likely
persist in the east a bit longer. Overall, not expecting much in
terms of additional snow accumulation more than an inch through this
evening east of Munising. After a brief quiet period this afternoon
and evening, the aforementioned low amplitude clipper works its way
southeast across the northern Great Lakes tonight, swinging around
the periphery of a nearly semi-permenant closed low hanging out in
the Hudson Bay. Weak WAA/isentropic lift ahead of the clipper will
be the forcing mechanism for light snow that is set to spread across
the northern tier of the UP late tonight into tomorrow morning.
Model QPF isn`t too impressive, coming out between a trace to a tenth
of an inch per 6 hours where lake effect/enhancement may provide a
local boost in the Keweenaw and east. Combined with SLRs 15-20:1,
this yields snow totals by tomorrow afternoon less than an inch
across much of the central and western UP. Elsewhere, WSW flow may
be able to sneak in 2-4" in the Copper Country, while 1-3" will be
seen in the east, mainly from Luce county further into Chip/Mack.
Snowfall may be thwarted by a dry boundary layer beginning to take
shape as well as midlevel subsidence noted by forecast soundings.
Additionally, SW winds will be on the increase tonight as the
clipper`s 40-50kt LLJ works its way overhead. SW gales 35-40 kts
will be common on Lake Superior tonight before calming down around
sunrise.

For those that miss out on the light snowfall tonight, don`t worry!
The pattern through the rest of the weekend and into the coming week
is highly supportive of persistent NW flow aloft and embedded
clipper trains skirting through the Midwest and Upper Great Lakes,
the first of which quickly follows tomorrow night into Saturday
morning. This one takes a slightly southern track through N
Wisconsin, providing another round of light snow followed by a
reinforced shot of cold air and light lake effect snow to the
northwest wind snowbelts through the rest of the weekend. At this
time, lake effect snow aims to be on the lighter side, potentially
providing the NW wind snowbelts with an additional 1-3" (locally
higher under stronger, more persistent bands) despite supportive
delta-Ts pushing 25C given dry air within the boundary layer.

Looking further into the midweek period, operational models and
their ensemble counterparts continue the NW flow aloft clipper train
across the area, supporting additional periods of accumulating
system and lake effect snow.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1251 PM EST Thu Dec 4 2025

A period of VFR conditions will persist through the remainder of the
daylight hours this afternoon. However, MVFR cloud cover will return
to the terminals later this evening and tonight, along with our next
shot for a period of light snow with the next weather system. It
still appears the best shot for some IFR VSBYs in snow will be at
KCMX mid to late this evening. Otherwise, expect some scattered
flurries to linger into early Friday morning.

Winds will initially remain light from the southwest early this
afternoon, however, speeds are expected to increase and become gusty
into this evening as the surface gradient strengthens ahead of low
pressure tracking eastward across Ontario. Peak wind gusts of 30-35
kt are likely this evening into tonight, before easing into Friday
morning.

&&

.MARINE...
Issued at 257 PM EST Thu Dec 4 2025

Southwest winds ahead of the next Clipper Low will ramp up in the
west this evening to gales of 35 kt, spreading across the rest of
the lake up to 40 kt tonight. Freezing spray rates will be more
moderate with the gale this evening through tomorrow. Waves quickly
ramp up to 9-13 ft tonight for the open waters surrounding Isle
Royale and Michipicoten Island. Tomorrow, wind gusts fall to near 20
kt and waves fall to near 4 ft. Saturday morning, post-frontal
northwest winds will ramp up to 30 kt, with chances of a brief 35 kt
gale around 40 percent. The weather pattern into next week looks to
continue with periodic Clipper Lows that will bring either increased
southwest winds ahead of it and/or gusty northwest winds in its wake.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
  Gale Warning until 4 AM EST /3 AM CST/ Friday for LSZ162-
     240>242-263.

  Gale Warning from 7 PM this evening to 7 AM EST Friday for
     LSZ243>251-264>267.

Lake Michigan...
  Gale Warning from 10 PM this evening to 7 AM EST Friday for
     LMZ221-248-250.

&&

$$

DISCUSSION...BW
AVIATION...BW/LOT
MARINE...BW