Latest Duluth Area Text Forecast Discussion product from NWS:
500
FXUS63 KDLH 171014
AFDDLH
Area Forecast Discussion
National Weather Service Duluth MN
414 AM CST Wed Dec 17 2025
.KEY MESSAGES...
- Multiple rounds of strong winds are expected through this
week: this afternoon and evening (Wind Advisory in effect),
Wednesday afternoon and evening (southerly gusts 25-35 mph),
and through the day Thursday (northwest gusts 35-55 mph).
- A messy system will bring rain, freezing drizzle, and heavy
wet snow to the Northland late Wednesday afternoon through
Thursday. A Winter Storm Watch is in effect for the
Borderlands.
- Warm temperatures above freezing crash back down below zero
by Friday morning. Some areas could experience a flash freeze.
&&
.DISCUSSION...
Issued at 414 AM CST Wed Dec 17 2025
Gusty winds will continue to subside this morning in the wake
of an overnight cold front. Temperatures will rebound with
daytime highs in the middle 20s to middle 30s. Warm air
advection ahead of the next clipper will likely keep
temperatures climbing through this evening until another cold
front arrives early Thursday morning. As a result the 24 hour
high temps for some locations in Wisconsin were reached shortly
after midnight. For the rest of the Northland 24 hour high temps
will be reached shortly before midnight tonight.
The 17.00Z forecast models seem to be struggling a bit with
sensible weather impacts with tonight and Thursday`s clipper.
Abundant Pacific moisture will accompany the wave as it
propagates across the Plains and Prairies this afternoon and
tonight. Similar to last night, the 00Z GFS took a more
southerly trajectory with the surface low and shifted
precipitation south compared to the other models. Also similar
to last night, the new 17.06Z GFS came into better agreement
with the ECMWF and CMC. NAM remains a little slower and farther
north than the global models.
Precipitation tonight will be essentially in two regions, a
broad area of light snow near the Canadian border north of the
low track, and a band of precipitation associated with the cold
front as it races eastward tonight and Thursday morning. A
prominent "dry slot" of stratospheric air will be pulled into
the system behind the cold front. With the loss of ice aloft,
there is a risk of drizzle or freezing drizzle after the first
round of precipitation with the cold front. A glaze up to a few
hundredths of an inch of ice accumulation can be expected IF the
freezing drizzle develops. There is ample forcing for ascent
north of the low track.
Temperatures will start out above freezing aloft over much of
the Northland. The initial precipitation type may be rain or
freezing rain. The column will quickly cool below freezing due
to diabatic and evaporative cooling allowing the precipitation
to change to all snow. Snow ratios will be low initially and
will increase to 13-17 to 1 early Thursday morning. Thus the
first several hours of snow will be heavy and wet with a change
to drier snow as cold air advection increases late Thursday
morning.
Strong winds will follow the surface low. Low-level lapse rates
will steepen due to the strong cold air advection. A strong LLJ
will follow the surface low late Thursday morning through early
Friday morning. The steep lapse rates will allow some of that
momentum to mix down to the surface. The combination of snow and
strong winds may create power outages north of the Iron Range
and into the Arrowhead. The drier snow on Thursday may be lofted
and cause visibility reductions.
With more dry air being ingested into the system than earlier
forecasts, the range of potential snow amounts remains high. The
highest amounts should be found north of a line from Cass Lake
to Silver Bay where widespread 2 to 5 inches are forecast. A few
spots near the Canadian border may pick up around 6 inches. And
portions of Cook and northern Lake County may see as much as 7
to 8 inches. While model guidance and ensemble solutions suggest
a wide range of possible snow totals, the final totals will
likely not be spread as broadly. The system will be moving
quickly and the best forcing for ascent will be located below
the dendritic growth zone. That forcing will also pass by any
given location quickly, limiting the period of the highest snow
rates. There may be an hour or two of 0.5 to 1 inch rates.
Strong cold air advection Thursday and Thursday night will see
temperatures drop below freezing, potentially reaching the teens
below freezing for many locations. Wind chills will definitely
be a concern as a result of the strong winds.
The system moves out of the region Friday morning allowing us
to catch a short breath before the next clipper arrives Friday
night and Saturday. That system has trended slightly farther
north today which has decreased the snow amounts from that
system. The swath of snow will be narrow once again and slight
changes in the storm track will bring several inch changes in
forecast snow amounts.
Sunday through the middle of next week will see temperatures
near normal. There remains an indication of another clipper
moving through the region in the Monday night through Tuesday
timeframe. However, the latest suite of guidance features less
moisture for that system and a more northerly track which may
miss the Northland.
&&
.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1213 AM CST Wed Dec 17 2025
Gusty northwest winds will continue to slowly weaken early this
morning. MVFR stratus over the region will give way to mostly
clear skies from northwest to southeast early this morning. A
few snow flurries will accompany the stratus, though VFR
visibility is expected. Winds back southerly today ahead of the
next clipper arriving tonight. A strong southwesterly low-level
jet will develop ahead of a cold front late this afternoon and
evening. Thus we have LLWS at all of the terminals. As surface
low pressure propagates into northern Minnesota by 06Z,
precipitation chances will increase during the evening at INL,
HIB, and DLH. Warm temperatures aloft may result in a brief
period of freezing drizzle or freezing rain just as
precipitation begins. The column will cool quickly and change to
all snow within an hour or two of the onset of precipitation.
&&
.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 1210 AM CST Wed Dec 17 2025
Update 1213 AM CST Wed Dec 17:
We extended the Gale Warnings for Taconite Harbor to Duluth, MN
to Bayfield, WI and the Outer Apostle Islands until 4 AM. Gusty
winds were still observed along the North Shore. Air
temperatures are much cooler than the lake surface temperatures
and as such we expect efficient vertical mixing over the water.
The mixing will allow higher momentum air aloft to reach the
surface.
Previous 321 PM CST Tue Dec 16:
Numerous rounds of gales and possibly storm force gusts are expected
through this week. The first round arrives through today and this
evening with southwest winds becoming northwest behind a mostly dry
front. The strongest winds should be along the North Shore but all
of Western Lake Superior will likely see gusts in excess of 35
knots. Gusts in excess of 45 knots are possible for the North Shore.
A Gale Warning is in effect. Wind should die fairly quickly going
into Wednesday morning but the lull wont last long, with southerly
winds picking up through Wednesday afternoon. Another period of gale
force gusts is possible here too. Into Thursday morning those winds
remain strong but become northwesterly and strengthen even further
through the day Thursday. By Thursday afternoon and evening gale
force winds are likely and storm force gusts are possible,
especially for the North Shore. A Gale Watch is in effect. Winds
should calm going into Friday morning.
For the open water discussion, refer to the NWS Marquette Area
Forecast Discussion at weather.gov/mqt.
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...Winter Storm Watch from late tonight through Thursday evening
for MNZ010-011.
Winter Storm Watch from late tonight through late Thursday
night for MNZ012-021.
WI...None.
MARINE...Small Craft Advisory from 4 PM this afternoon to 4 AM CST
Friday for LSZ121.
Small Craft Advisory from 8 PM this evening to 2 PM CST
Thursday for LSZ140>142.
Gale Warning from 2 PM Thursday to 4 AM CST Friday for
LSZ140>144.
Small Craft Advisory from 4 PM this afternoon to 2 PM CST
Thursday for LSZ143>147.
Gale Warning from 2 PM to 10 PM CST Thursday for LSZ145>148-
150.
Small Craft Advisory from 4 PM this afternoon to 8 PM CST this
evening for LSZ148-150.
Gale Warning from 8 PM this evening to 4 AM CST Thursday for
LSZ148-150.
&&
$$
DISCUSSION...Huyck
AVIATION...Huyck
MARINE...Levens
NWS DLH Office Area Forecast Discussion
