922
FXUS63 KDLH 252121
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
321 PM CST Tue Nov 25 2025

.KEY MESSAGES...

- Heavy snow continues to move northeast tonight. Blizzard
  conditions are possible along the South Shore. Gusty winds
  also expected elsewhere could lead to blowing snow.

- Snow enhancement from a gravity wave and lake effect snow will
  lead to higher snow totals across northwest Wisconsin,
  particularly at higher elevations.

- After this system, cooler air is here to stay for the rest of
  the forecast period. Highs will be in the 20s and lows in the
  teens for the rest of the week. Low temperatures near zero are
  expected Sunday night.

&&

.DISCUSSION...
Issued at 211 PM CST Tue Nov 25 2025

This large low pressure system, currently located over southern
Minnesota, continues to make its way northeast towards the
Northland. This system is already producing snow across eastern
ND/SD with visibilities less than a mile. If those conditions
continue, some additional Blizzard Warnings may be needed for
portions of the Northland. Particularly, as we head into this
evening, a band of frontogenesis combined with strong forcing
and divergence is expected to strengthen further this band of
enhanced snowfall in the TROWAL region of the system. It has
shifted south again, leading the placement of this band to
likely be mostly over NW Wisconsin, and possibly just clipping
the North Shore. Additionally, as flow begins to turn to the
northwest, CAMS are showing a potential for a gravity wave to
set up over Douglas/Bayfield counties, which could lead to over
an inch per hour rates at times in localized areas. This setup
can keep this gravity wave going as late as Wednesday afternoon.
The snowfall rates (around 1"/hr) and winds will be sufficient
for meeting a blizzard warning criteria, but whether the
visibility is lowered to below a quarter mile for an extended
period of time is still uncertain in these areas with the
exception of Douglas and Bayfield counties. With the gravity
wave, confidence is higher for those higher snowfall rates and,
as a result, visibilities below a quarter mile. Blizzard
Warnings have been issued for both counties.

A break in the snowfall may be seen in our southern line of WI
counties this evening into tonight as the dry slot moves east
just to our south. The exact track of the dry line should stay
largely to the south, so a break in precipitation, if any,
should be brief.

Early Wednesday morning, as winds shift further to the northwest,
lake effect snow will also begin over northwest Wisconsin.
Since we have had temperatures averaging above normal for the last
few weeks, Lake Superior water temperature is still in the 40s. With
the CAA, the air mass will be much colder than the water, which will
enhance the lake effect snow further along with sufficient mid
level lapse rates increasing throughout the morning (6-9 C/km).
As with Douglas and Bayfield counties, confidence has increased
that the combination of enhanced snowfall rates (>= 1"/hr) and
wind gusts will create visibilities less than a quarter mile for
an extended period of time. So, Blizzard Warnings have been
issued for Ashland and Iron counties as well. Snowfall across
the region will begin to exit Wednesday morning, but lake effect
snow will continue for Ashland and Iron counties through
Wednesday and into the latter half of the week.

Overall, a majority of the area will see an additional 6"+
except for west of Ely down to Brainerd. Areas under the TROWAL
could see up to a foot of snow, and the gravity wave/lake
enhancement across the South Shore counties will lead to 10-15
for most, with bullseyes of 20"+ in northern Iron County. Since
snowfall has shifted south again, and some areas are not seeing
snow as far north as previously forecasted, opted to end the
Winter Weather Advisory for Koochiching county and downgraded
the Winter Storm Warnings for northern Itasca and northern St.
Louis counties to Winter Weather Advisories.

Winds throughout the system will be strong as well, increasing
initially from the northeast before backing to the northwest.
Gusts up to 35 mph are expected for most, especially on
Wednesday. The North and South Shores could see wind gusts
upwards of 45 mph overnight and Wednesday with the most intense
CAA into the region. These elevated winds could lead to any
snow that hasn`t already compacted to be blown around. A cool
down is also expected behind the system, where we will have
temperatures below freezing for the rest of the forecast period.
High temperatures will be in the twenties and possibly even the
teens by next week, and lows will be in the teens decreasing to
around zero next week as well.

There is the potential for another system to bring light snow
this weekend. Global models have started to have better
agreement on the track of the system, which is currently to our
south. Most of the moisture and forcing will remain south as
well, so any snow accumulations are expected to be light with
the current forecast. Light lake effect snow on the back of
this system is looking likely as well.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1125 AM CST Tue Nov 25 2025

Rain and snow are currently ongoing throughout the Northland.
Rain is not expected to lower visibilities at HYR unless a band
of moderate rainfall moves over, which should move over the
terminal by the top of the hour. Snow will continue to move
eastward throughout the day, bringing IFR ceilings and
visibilities, with conditions lowering to LIFR at times. Winds
will also be strong, with gusts continuing to increase
throughout the day, peaking tonight into Wednesday with 30+ kt
gusts. Snow should end west to east tonight through Wednesday
early afternoon.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 211 PM CST Tue Nov 25 2025

Winds continue to increase this afternoon over Lake Superior as
the system bringing heavy snow approaches. First, winds will be
out of the northeast today and this evening, then backing to
the northwest overnight tonight. Gusts upwards of 40 kts are
expected, especially tonight into Wednesday. Waves will continue
to builds as well, reaching 7-10 ft along the South Shore by
this evening and increasing to 10-15 ft around the Apostles and
Bayfield Peninsula overnight. Gale Warnings are in effect for
all western Lake Superior near shore waters into Thursday
morning.

For the open water discussion, refer to the NWS Marquette Area
Forecast Discussion at weather.gov/mqt.

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...Winter Weather Advisory until 6 AM CST Wednesday for MNZ011-
     018.
     Winter Storm Warning until midnight CST Wednesday night for
     MNZ012-019>021-037.
     Winter Storm Warning until noon CST Wednesday for MNZ025-026-
     033>036.
     Winter Storm Warning from 6 PM this evening to 6 PM CST
     Wednesday for MNZ038.
WI...Blizzard Warning from 6 PM this evening to midnight CST
     Wednesday night for WIZ001-002.
     Blizzard Warning from 6 PM this evening to 6 AM CST Thursday
     for WIZ003-004.
     Winter Storm Warning from 6 PM this evening to midnight CST
     Wednesday night for WIZ006>009.
MARINE...Gale Warning until 6 AM CST Thursday for LSZ121-140>148-150.

&&

$$

DISCUSSION...KML
AVIATION...KML
MARINE...KML