487
FXUS63 KMQT 251755
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
1255 PM EST Tue Nov 25 2025

.KEY MESSAGES...

- Winter Storm Warnings and Watches are in effect for much of
  the UP as a deepening low pressure tracks across the UP
  tonight into Wednesday, with an eventual transition to lake
  effect snowfall. Chances of 12 inches or more of snow are
  around 100% percent across the north-northwest wind snow belts
  of the western UP by Thanksgiving, with some spots potentially
  receiving 2 to 3+ feet.

- Wind gusts of 25-35 mph are expected Wednesday, with some
  gusts to 50 mph or more possible over the Keweenaw, the higher
  elevations of Baraga County, and along the lakeshore of
  Marquette and Alger counties. The combination of wind and
  moderate to heavy snowfall could make Thanksgiving holiday
  travel very difficult to downright impossible at times. The
  high winds could create some power outages.

- Given the high snowfall rates and strong winds, blizzard
  conditions are possible across Gogebic, Ontonagon, northern
  Houghton, and Keweenaw counties late tonight through Wednesday
  (30 to 50% chance).

- Gales up to 45 kt are expected (70-90%) on Lake Superior this
  evening through Thanksgiving, with Storm-Force gust to 50 kt
  possible (40 to 60% chance). Wave heights of 12-18 ft are
  expected, with some spots near Stannard Rock and between
  Marquette and Grand Marais seeing up to 18-21 ft waves.

- Some minor lakeshore flooding and beach erosion is possible
  along the Lake Superior shoreline late tonight through
  Thanksgiving given the strong winds and waves coming off of
  the lake.

&&

.DISCUSSION...
Issued at 400 AM EST Tue Nov 25 2025

As two shortwave lows, one bringing snowfall to the Northern Plains
this morning and another lifting north from the Southern Plains and
Mid-Mississippi Valley, phase with one another today over the Upper
Mississippi Valley, expect light rainfall (which has already begun
over the southern half of the U.P.) to spread into the rest of Upper
Michigan today. With overcast skies and rainfall overhead, expect
highs today to range from the upper 30s in the west to the mid 40s
in the south central and east.

The winter weather action generally begins this evening over the
western U.P. as the now-phased-and-deepening low allows moisture-
rich Gulf air to wrap around and over the just-sub-freezing air
across the western third of the Upper Peninsula. This may occur
earlier today too, with some of the CAMs guidance (such as the
NAMNest) bringing moderate to borderline heavy snowfall across the
west as soon as early this afternoon. However, with most guidance
keeping temperatures just right above freezing throughout the
daylight hours today across the area, confidence is lacking on
whether the developing TROWAL of the low will be able to bring high
enough snowfall rates to overcome the above-freezing air at the sfc
via dynamic cooling of the atmospheric profile (thinking around 30%
or less on accumulating snow until the evening hours). However,
snowfall accumulation chances rapidly increase over the western U.P.
once the sun sets and colder air starts to slowly make its way
eastward across Upper MI tonight. As the low continues to deepen as
it lifts northeast towards Lake Superior tonight, the TROWAL of the
low will bring snowfall rates of 1+ inch/hour across much of the
western U.P. (50+% chance for every hour tonight through Wednesday
according to the 00z HREF; 90+% chance according to the NBM). With
colder air coming in from the north and the pressure gradient around
the low tightening with time, an upslope and lake enhancement
component will assist in keeping the snowfall rates high tonight
into Wednesday across the west and Keweenaw. In addition, due to the
low deepening and the pressure gradient around it tightening, expect
the winds over the west to drastically increase, with the incoming
cold air advection helping to bring the much higher winds aloft to
the sfc, even during the overnight hours. Gusts as high as 50 (or
more) mph could be realized over the Keweenaw, higher elevations of
Baraga County, and even near the lakeshores of Marquette and Alger
counties later Wednesday. Meanwhile, frequent gusts of 35 mph or
greater are expected for several hours across the far west. Thus, we
very well might see Blizzard conditions across Gogebic, Ontonagon,
northern Houghton, and Keweenaw counties late tonight through
Wednesday, as all the criteria for a Blizzard Warning seems to be
met (the HREF shows a 30 to 50% chance for several hours tonight
through Wednesday). However, decided to hold off on issuing a
Blizzard Warning for these counties for now given that the onset of
the heavy snowfall is about 18 hours away; will let the dayshift
decide if a Blizzard Warning is warranted for these areas.

As the low lifts into Lake Superior Wednesday and away towards
northern Quebec later in the day, expect the transition from rain to
snowfall to continue west to east. As the TROWAL progresses eastward
with time, the heavier snowfall looks to be seen over Marquette
County during the morning hours (after the sunrise) and the eastern
U.P. by the afternoon as said TROWAL slowly starts to weaken with
time (occlusion of the low i.e. loss of Gulf moisture). As this
happens, expect the transition over to lake enhanced snowfall across
the area, and eventually to pure lake effect by Wednesday night.
Recent guidance has shifted the winds more north-northwesterly this
morning, which in turn would bring a little more snowfall to the
north-central as it would have more Lake Superior fetch to work
with. In addition, with -15C 850mb air moving over 5C Lake Superior
sfc waters, some guidance is picking up on some modest MUCAPE
values, potentially even up to 100 J/kg. Thus, while not expected,
there is up to a 10 to 15% chance that some thundersnow will be
realized over the north-northwest snowbelts Wednesday into
Thanksgiving morning in the lake enhanced to lake effect snow bands.
Given the strong delta-Ts and troughing persisting through
Thanksgiving, moderate to heavy lake effect snowfall and blowing
snow looks to continue through the holiday. Thus, given the system
and lake enhanced/effect snowfall, some spots over the western U.P.
could see 2 to 3+ feet of snowfall before the end of the
Thanksgiving weekend. Meanwhile, areas of the north central and east
could see 6 to 24 inches, with some spots potentially seeing over
24+ in the east (I would suspect between Marquette and Munising).
Overall, thinking this will be a storm to remember, especially for
the west. If you can, get your Thanksgiving travel and shopping done
today; you do not want to be out in this tonight through
Thanksgiving as travel will be very difficult to downright
impossible at times. If you are going to travel, take it slow and
make sure to bring some water, food, a flashlight, and a blanket
with you in case you get stuck; conditions will be ideal for car
accidents. Also, some power outages aren`t out of the question
either given the strong winds. If you do experience an outage, be
prepared for the power to be out for several hours as the hazardous
winter weather will persist for at least a couple of days. Some
minor lakeshore flooding is also possible along the Lake
Superior shoreline late tonight through Thanksgiving given the
strong winds and waves from the lake.

As the troughing weakens late this week into this weekend, expect
the lake effect snow to lighten up over the north-northwest snow
belts Thursday night through Friday night, with the lake effect snow
potentially even ending over the west half by Saturday morning.
Looking ahead, it does seem like we will have another shortwave
bring some accumulating snowfall to the area late this weekend;
however, the impacts don`t look to be nearly as significant in
comparison to the storm that`s incoming today/tonight. Expect the
colder than normal temperatures to persist into early next week.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1255 PM EST Tue Nov 25 2025

As a low pressure deepens as it passes through the UP throughout
this TAF period, SHRA turns to SHSN from west to east, bringing with
it significant periods of LIFR to minimums at all sites, with some
periods of IFR possible.

SAW is already at airport minimums as the combination of gusty winds
out of the northeast moving upslope with rain-moistened air causing
low ceilings and FG. Some improvement to LIFR is possible (~50%)
this afternoon with some more dry surface air reaching the terminal,
but after sunset, airport minimum ceilings and occasional low vis
will return. As winds become more northerly and are not as directly
upslope tonight into Wednesday, some improvement in the ceiling is
expected, but a transition to SHSN in conjunction with gusts to 30+
kt will create a BLSN threat which will bring 20-40% chances of
blizzard conditions to the terminal.

IWD and CMX are more likely (60-80%) to see blizzard conditions
overnight into  as winds at CMX especially gust to over 40 kt and
both sites will see more direct upslope flow when winds become more
northerly to northwesterly as well as better SHSN rates.

&&

.MARINE...
Issued at 418 AM EST Tue Nov 25 2025

As two shortwaves, one moving through the Northern Plains and one
lifting from the Mid-Mississippi Valley, phase with one another
today over the Upper Mississippi Valley, the winds over Lake
Superior will progressively increase from the northeast, with the
far west starting to see gales to 35 kts potentially as early as
late this afternoon. As the phasing and deepening low lifts towards
the lake tonight, expect the winds to progressively back to the
north with time, increasing to gales of 35 to 45 kts, with a few
storm force gusts possible over the north central late tonight (40
to 60% chance). As the low moves through the eastern lake Wednesday
and lifts towards northern Quebec later in the day, expect the winds
to become more north-northwesterly in the wake of the low. While
winds look to weaken over the western lake Wednesday night, the high-
end gales (with potentially a few storm force gusts) looks to
continue into Thanksgiving. As the troughing pattern weakens
Thanksgiving through late this week, expect the winds to lighten up
with time, with the gales finally ending late Thursday night.
Throughout the gale event, some light freezing spray will be
possible across the waters from late Wednesday through Thursday
evening. In addition, expect waves of 12 to 18 feet across the
waters, with some areas near the tip of the Keweenaw, near Stannard
Rock, and from Marquette to Grand Marais, MI potentially seeing wave
heights or 20+ ft. Winds continue to weaken through Friday,
eventually becoming 20 kts or less by Friday night. The light winds
look to continue until Sunday when a shortwave lifts back into the
western Great Lakes region.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Winter Storm Warning from 7 PM EST /6 PM CST/ this evening to
     7 PM EST /6 PM CST/ Wednesday for MIZ001>004-009-010-084.

  Lakeshore Flood Advisory from 4 AM Wednesday to 1 PM EST
     Thursday for MIZ001.

  Lakeshore Flood Advisory from 1 AM EST /midnight CST/ to 7 PM
     EST /6 PM CST/ Wednesday for MIZ002-009.

  Lakeshore Flood Advisory from 7 AM Wednesday to 1 AM EST
     Thursday for MIZ003.

  Lakeshore Flood Advisory from 7 AM Wednesday to 1 PM EST
     Thursday for MIZ005.

  Winter Storm Warning from 7 AM to 10 PM EST Wednesday for
     MIZ005.

  Winter Storm Warning from 10 AM Wednesday to 7 AM EST Thursday
     for MIZ006.

  Lakeshore Flood Advisory from 1 PM Wednesday to 1 AM EST
     Friday for MIZ006.

  Winter Storm Watch from Wednesday afternoon through Thursday
     evening for MIZ007-013-014-085.

  Lakeshore Flood Advisory from 1 AM Thursday to 1 AM EST Friday
     for MIZ007.

Lake Superior...
  Gale Warning from 4 PM Wednesday to 1 AM EST Friday for LSZ251-
     267.

  Gale Warning until 7 AM EST /6 AM CST/ Thursday for LSZ162.

  Gale Warning from 10 PM EST /9 PM CST/ this evening to 7 AM
     EST /6 AM CST/ Thursday for LSZ240>242.

  Gale Warning from 10 PM this evening to 1 PM EST Thursday for
     LSZ243-246.

  Gale Warning from 10 PM this evening to 7 PM EST Thursday for
     LSZ244-245-264-265.

  Gale Warning from 1 AM Wednesday to 1 PM EST Thursday for
     LSZ247-248.

  Gale Warning from 10 AM Wednesday to 1 AM EST Friday for
     LSZ249.

  Gale Warning from 1 PM Wednesday to 1 AM EST Friday for LSZ250.

  Gale Warning from 7 PM this evening to 1 PM EST Thursday for
     LSZ263.

  Gale Warning from 1 AM Wednesday to 1 AM EST Friday for LSZ266.

Lake Michigan...
  Gale Warning from 4 PM Wednesday to 1 AM EST Friday for LMZ221-
     248-250.

&&

$$

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