192
FXUS63 KMQT 050525
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
1225 AM EST Fri Dec 5 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 /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1224 AM EST Fri Dec 5 2025

Conditions have deteriorated to at least MVFR at all sites as the
next clipper system approaches the TAF sites. However, IWD and CMX
are also expected to fall to IFR/LIFR later this morning, especially
CMX where lake enhancement will help to intensify any snow bands. In
addition, will continue to carry a LLWS threat at IWD and SAW early
this morning as a 40-50 kt low level jet precedes the aforementioned
clipper system. At the surface, southwesterly winds will gust to 25
to 30 kts at all TAF sites through at least Fri 10Z, decreasing
toward daybreak. IFR/MVFR conditions will persist at both IWD and
CMX through the morning with SAW trending more toward MVFR/VFR.

&&

.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 7 AM EST this morning for LSZ243>251-
     264>267.

  Gale Warning until 4 AM EST /3 AM CST/ early this morning for
     LSZ162-240>242-263.

Lake Michigan...
  Gale Warning until 7 AM EST this morning for LMZ221-248-250.

&&

$$

DISCUSSION...BW
AVIATION...TDUD/GS
MARINE...BW