602
FXUS63 KMQT 170723
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
223 AM EST Mon Nov 17 2025

.KEY MESSAGES...

- Lake effect snow diminishes and winds decrease today over the
east, though 20-50% chances remain for an additional 1-3 inches of
snowfall for Luce County.

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

&&

.DISCUSSION...
Issued at 222 AM EST Mon Nov 17 2025

KMQT radar returns at 05Z show mostly light northwesterly lake
effect snow, with individual weak convective cells evident over
eastern Lake Superior. Hi res model guidance suggests varying
degrees of NW wind LES maintaining over the east today, ranging from
a single dominant band over Luce County (HRRR), multiple weak bands
from Alger to Luce Counties (NSSL WRF), and weak cellular style LES
(NAM Nest) with the rest falling somewhere in between. Aloft, a
stacked, closed upper low is over New England while expansive
ridging resides over the Plains. Further upstream, a closed low is
over Utah while pronounced troughing is just off the coast of the
Pacific Northwest.

For today and tonight, weakening (but persistent) lake effect snow
will continue over the east. 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 over the eastern
portions of Lake Superior 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 relative to yesterday
show lesser lake-induced instability (around 200-300 J/kg) and
inversion heights around 5 kft with the depth of the moist layer
even further limited by significant dry air is present at the top
and bottom of the inversion, though there are still around 2 kft of
saturated air to work with. Soundings further west show
significantly more dry air, less instability, and even lower
inversion heights. Additionally, encroaching surface ridging will
further take away forcing that would help lake effect showers. With
all of these conditions showing lessening potential for impactful
lake effect snow, the Winter Weather Advisory has been cancelled,
though HREF LPMM plots show a potential for additional streaks of 1-
3 inch snowfall potential in rural Luce County.

For Tuesday, the aforementioned closed low currently over Utah is
expected to progress through the Plains and pass to the south of the
UP, keeping all of its precipitation out of the area. 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. As the trough
remains just upstream of the CONUS radiosonde network, ensemble
spread is understandably high, though the deterministic models have
trended southward with the path of the main surface feature.
Spaghetti plots show that an Alberta Clipper-type shortwave passing
through Ontario Friday morning may provide more impact to the UP,
though spread remains high in the amplitude and placement of such a
wave. With the complex interactions of modeled waves that are not
even on shore yet, 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 low pressure 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 clearing skies
following cessation of lake effect Tuesday morning, especially in
the typical cool spots (20-60% chances of NBM lows cooler than 15 F
in the interior west and central).

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1159 PM EST Sun Nov 16 2025

VFR conditions continue today as the lake effect cloud cover
bringing low-end VFR cigs over CMX and SAW ends by this afternoon.
While some flurries could be seen over CMX and SAW this morning,
they won`t effect flying conditions. Expect the winds to continue
dying down today as ridging builds in from the west.

&&

.MARINE...
Issued at 222 AM EST Mon Nov 17 2025

Encroaching high pressure has already ended gales across Lake
Superior, though northwest wind gusts will remain above 25 kt until
the midmorning hours today. Wind gusts fall below 20 kt overnight
tonight into Tuesday. Significant wave heights this morning will
fall to 4-7 ft for the east half (less in the west) and below 4 ft
overnight tonight into Tuesday lakewide. High pressure will then
keep wind gusts sub-20 kt until at least the late-week period. Then,
attention turns to multiple potential shortwave troughs that could
spawn surface low pressure systems. Confidence is low in the
details, but there is a 15-25% chance that a low pressure feature
could be accompanied by gale-force gusts.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.

&&

$$

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