797
FXUS63 KDLH 031120
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
620 AM CDT Wed Sep 3 2025

.KEY MESSAGES...

- Fall weather continues through late week with cool
  temperatures and persistent light rain shower chances.

- Brief snow showers are possible during the evening through
  late morning times each day.

- Areas of  frost are possible Thursday and Friday mornings.

- Slightly warmer weather late-weekend into early next week.

&&

.DISCUSSION...
Issued at 401 AM CDT Wed Sep 3 2025

At 08Z a cold front stretched from a tightly wound surface low
pressure located over far northern Lake Superior southwestward
across central Wisconsin to near the Iowa/Minnesota border. A
second cold front was located upstream over southern eastern and
southern Manitoba. An upper-level low pressure center was over
far northwest Ontario and northeast Manitoba. GOES-East water
vapor imagery revealed several vorticity maxima rotating through
the upper-level trough northwest Wisconsin, northwest Ontario,
and southern Manitoba. Low stratus was found across the region
in cold air advection behind the first cold front. Partial
clearing was over northwest Minnesota ahead of the second cold
front. mPING and automated station reports indicated drizzle and
light rain showers over the Northland. The low altitude of the
showers over northern Minnesota were generally below the
sampling altitude of the KDLH WSR-88D and thus were not
appearing on radar. CASWL near Winnipeg featured an area of rain
showers associated with the second cold front. Temperatures
were in the upper 40s to upper 50s across the Northland.

Today and tonight...

The second cold front is forecast to rotate southeastward
across the Northland today. Cold air advection and gusty winds
will continue. Most areas likely reached their high temperature
for today around midnight. Temperatures today will be generally
falling with a brief warmup during early afternoon. Afternoon
high temperatures will be in the upper 40s in the inland
Arrowhead to the upper 50s from Brainerd to Spooner. The second
cold front will bring a slightly more organized and persistent
area of rain showers southeastward through the Northland today.
Additional showers are likely behind that front as well this
afternoon into tonight. As temperatures fall overnight, showers
may become a mix of rain and snow. A thin coating of snow may
survive through sunrise before melting shortly thereafter. Frost
is possible overnight into Thursday morning, though clear skies
and calm winds would likely be required.

Thursday through Saturday...

While the upper-level low pressure system loiters over
northeast Ontario, another shortwave trough will propagate
southeastward across the Canadian Prairies and into the northern
Plains Thursday. That trough will be accompanied by a surface
cold front. Widespread rain showers will likely overspread the
Northland during the day as that wave moves through the region.
There may be a few small pockets of snow in the tallest showers.
High temperatures will be in the low to upper 50s. Rain, and
possibly snow showers, will persist Thursday evening as the
trough rotates eastward across Wisconsin. There will be another
potential for areas of frost provided winds can relax and skies
clear.

Friday will see another shortwave trough rotate southeastward
across the region as the upper-level low begins to kick farther
east. Cold air advection and cyclonic flow aloft will bring
another day of cloudy skies and rain showers. Temperatures will
be in the 50s once again.

High pressure is forecast to move into the region for Saturday
and influence of the upper-level low will begin to relax.
Increasing sunshine and lighter winds will allow temps to tick
upward a few degrees into the middle 50s and low 60s.

Sunday through next Wednesday...

Low-level winds will back westerly and perhaps southwesterly on
Sunday and allow warmer temperatures to return. Highs are
expected to reach the upper 50s to middle 60s. A shortwave
trough may propagate through the Northland early next week and
bring a chance of showers and thunderstorms. Temperatures will
continue to trend warmer Monday and Tuesday, near normal for the
second week of September.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 620 AM CDT Wed Sep 3 2025

Widespread MVFR conditions are forecast today with pockets of
VFR ceilings. Scattered rain showers are likely and may briefly
drop visibility to MVFR. Winds will be gusty from the north and
northwest. Partial clearing is possible tonight at BRD while
MVFR ceilings persist elsewhere.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 401 AM CDT Wed Sep 3 2025

Strong and gusty northwest winds are forecast today in the wake
of a strong cold front. Winds of 10 to 20 knots are forecast
with gusts of 18 to 27 knots. Waves of the South Shore waters
will build to 2 to 7 feet by late afternoon. Winds may weaken a
bit overnight while generally remaining hazardous to smaller
vessels. Winds remain strong and gusty on Thursday and the Small
Craft Advisory was extended to late Thursday afternoon. Another
Small Craft Advisory will likely be needed for portions of the
waters Friday.

Intermittent rain showers are forecast today through Friday.
With the air moving over the water being colder than the lake
surface water temperatures, the showers may intensify when
moving over the lake. There is also a potential for waterspouts
with the strongest showers.

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

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
MARINE...Small Craft Advisory until 5 PM CDT Thursday for LSZ121-
     140>148-150.

&&

$$

DISCUSSION...Huyck
AVIATION...Huyck
MARINE...Huyck