337
FXUS63 KMQT 160949
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
449 AM EST Sun Nov 16 2025

.KEY MESSAGES...

- Breezy today, especially along the Keweenaw and near Lake
Superior. Northwest gales to around 35 knots are expected over
central/eastern Lake Superior into tonight.

- A Winter Weather Advisory remains in effect for Luce County as
chances of 4+ inches of snow are around 40-60%. Moderate to heavy
snowfall rates in conjunction with gusty winds could make travel
difficult along the M-28 corridor for end-of-weekend travel and for
the Monday morning commute.

- High pressure brings quieter weather for most of this week with
highs above freezing and lows below freezing.

&&

.DISCUSSION...
Issued at 448 AM EST Sun Nov 16 2025

KMQT radar returns this morning show northwesterly lake effect snow,
with more coverage over the central UP than initially expected. Hi
res model guidance suggests two main bands of snowfall this morning,
which lines up with radar returns. The KMQT radar is showing a band
intersecting Alger County while the CASMR radar is highlighting good
snow rates up to 1"/hr over Chippewa County and far northeast Luce
County. Aloft, a stacked, closed upper low is over Quebec while
expansive ridging remains over the Rockies. Further upstream, a
closed low is over southern California while pronounced troughing is
just off the coast of the Pacific Northwest.

For today and tonight, the lake effect snow will be the impactful
weather of note. Lake Superior continues to cool, though it remains
slightly warmer than normal still at around 7-8 C. With cool
northwesterly flow aloft, 850mb temperatures are forecast to be
around -10 C, plenty cool enough to have a temperature profile
supportive of lake effect snow. Model soundings around Grand Marais,
MI suggest lake-induced instability around 400-500 J/kg with
inversion heights around 7 kft, though the depth of the moist layer
is suspect as significant dry air is present at the top and bottom
of the inversion, though there are still multiple thousand feet of
saturated air to work with. Soundings further west show
significantly more dry air. Given the longer fetch down Lake
Superior and some Lake Nipigon connection, the eastern Lake Superior
NW wind LES band is preferred in this setup instead of a multi-band
setup spanning much of the lake. Given the above factors, there is
high "boom or bust" potential in the east as some ingredients
suggest significant snowfall potential while others cap the
potential. The HREF suite suggests around 40-60% chances of
exceeding 4 inches of snowfall today, though up to 40 percent
chances of exceeding 8 inches and even some 10-20% chances of up to
1 foot of snowfall by 12Z Monday. These probabilities suggest that
if the band (which the HREF suggests around 20% chances of 1"/hr
rates) remains in one given location all day, a significant
accumulation could occur, but just 20 miles in either direction of
the band could see only a couple inches. In addition to the
impactful snowfall rates, the cold advection aloft will help mix
down wind gusts of around 30 mph to the surface (closer to 40 mph at
the Lake Superior shores), which will further complicate travel and
introduce the risk of blowing and drifting snow. With the expected
impacts to weekend travel through the M-28 corridor and Monday
morning commute, will elect to maintain the current Winter Weather
Advisory, though some attention should be paid to the next round of
hi res model guidance as additional clarity on the surface
convergence pattern could give a better indication on the potential
for that band to drop Winter Storm-threshold snowfall (8+ inches).

Lake effect snow then is expected to diminish throughout Monday as
dry air intrudes and ridging aloft/surface high pressure encroaches
on the UP. For Tuesday, the closed low currently over southern
California is expected to progress through the Plains and pass to
the south of the UP. Have elected to remove most PoPs in that time
period, though the NBM is confident enough in precipitation that
this forecast package will keep a token "slight chance" (around 15
percent) of rain and snow showers along the MI/WI state line
Tuesday. Uncontested ridging then takes hold, giving quiet weather
for the Wednesday period. Then, attention turns upstream to the
lagging trough that is just off the coast of the Pacific NW
currently. While the deterministic models are honing in on a
solution that sends a Rockies Low through the Central Plains and
towards the Great Lakes, ensemble solutions are all over the
place. Spaghetti plots show a significant range in the evolution
of that trough, with the potential for the trough to split into
a closed Four Corners low and a Canada/US border-riding
shortwave, or for a more simple textbook Colorado Low-type
setup. Additionally, shortwaves in the vicinity of Hudson Bay
could further complicate the forecast. Therefore, confidence in
the details of the forecast into next weekend is low. For now,
highly impactful weather is not expected outside of an ensemble
outlier or two, though given the sheer number of potential
features, a wetter pattern is expected around that period. For
this week, expect highs above freezing (mid 30s to low 40s), and
lows below freezing (20s to low 30s), with the coolest
temperatures expected with the cold advection Monday morning in
the interior west (30-60% chances of lows in the teens).

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1237 AM EST Sun Nov 16 2025

Low-end VFR cigs look to hold on over the TAF sites tonight as
lake- effect cloud cover moves through the area. Some flurries
could be seen at CMX and SAW from time to time, but it shouldn`t
lower conditions below VFR (MVFR or lower chances limited to
15-25% or less at each of the terminals). Thinking any lake
effect cloud over IWD early this morning will erode away after
dawn. The gusty NW winds continue through the day today before
calming down this evening.

&&

.MARINE...
Issued at 448 AM EST Sun Nov 16 2025

Northwesterly gales continue across eastern Lake Superior this
morning as cold air aloft brings down gusts to 35-40 kt down to the
surface. Long duration winds along the long NW/SE fetch of Lake
Superior will support significant wave heights of 12-14 ft from
Caribou Island to Pictured Rocks National Lakeshore, with waves
across the central lake around 10 ft and around 4 ft in the west.
Winds will fall below gales tonight, below 25 kt Monday morning, and
below 20 kt Monday evening. Waves will similarly fall with time,
with waves falling below 8 ft Monday morning and below 4 ft by late
Monday night. With high pressure expected for much of the next week,
winds look to remain below 20 kt. Late in the week into the weekend,
a complex weather setup may support a low pressure passing through
the Great Lakes. Confidence is low in the details, but there is a 10-
20% chance that a low pressure feature could be accompanied by gale-
force gusts.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Winter Weather Advisory until 7 AM EST Monday for MIZ007.

Lake Superior...
  Gale Warning until 10 PM EST this evening for LSZ249>251-266-
     267.

Lake Michigan...
None.

&&

$$

DISCUSSION...GS
AVIATION...TAP
MARINE...GS