015
FXUS63 KDLH 241821
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
121 PM CDT Sun Aug 24 2025

.KEY MESSAGES...

- Hazardous conditions to small craft for all western Lake
  Superior nearshore waters today.

- Frost Advisory for the Borderlands, Arrowhead and Iron Range
  of Minnesota late tonight into Monday morning.

- Frost potential will expand across a greater portion of
  northeast Minnesota and northwest Wisconsin Monday night into
  Tuesday morning.

- For late this week and into the weekend, generally quiet
  weather is expected with high temperatures trending a bit
  below normal in the lower to mid 70s.

&&

.DISCUSSION...
Issued at 121 PM CDT Sun Aug 24 2025

A cool late August night is expected tonight across the
Northland, with good radiational cooling. Low level cloud cover
will decrease from north to south late this afternoon and into
the evening, with decreasing winds tonight as well as the
pressure gradient wanes. When coupled with a cool start to the
evening to begin with, widespread low temperatures in the upper
30s to the lower 40s are forecast, which is closer to the cooler
edge of guidance supported by statistical MOS given good
radiational cooling. The greatest potential for frost is across
the Borderlands, Arrowhead and Iron Range of northeast
Minnesota. Expanded the Frost Advisory to include central St.
Louis county, in addition to Koochiching, and interior Lake and
Cook counties for tonight into Monday morning. An expansion of
the Frost Advisory is possible, a 20 to 40 percent chance,
depending on trends through the evening. A couple points to
watch will be how quickly winds decrease and whether any
additional cloud decks move across the area in cyclonic flow.

Sunny and seasonably cool conditions are forecast on Monday with
high temperatures in the 60s with surface high pressure. Frost
will be a concern across a greater portion of the Northland
Monday night into Tuesday morning with a good radiational
cooling setup with cool and dry high pressure at the surface.

A cold front will move across the region Wednesday and Wednesday
night, bringing rain showers and perhaps a few thunderstorms
back into the forecast. Given modest buoyancy, severe weather
is not expected. Thereafter, northeast Minnesota and northwest
Wisconsin will be under a rather diffuse upper level pattern
between weak troughing across the east coast and modest ridging
across the west. The end result will be high temperatures
likely favoring a bit below normal in the low to mid 70s, with
precipitation potential having low predictability due to a wide
range of solutions of the timing and location of the shortwaves
in the diffuse upper level pattern.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 121 PM CDT Sun Aug 24 2025

Widespread MVFR conditions this afternoon in stratus and
scattered rain showers will clear from north to south across
northeast Minnesota and northwest Wisconsin late this afternoon
and evening. There have been a couple reports of low level wind
shear at KDLH, and have maintained this mention in the TAF for
the afternoon. Northwest wind gusts of 20-25kts will be common
across the area through sunset. VFR conditions are forecast on
Monday with surface high pressure.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 121 PM CDT Sun Aug 24 2025

Gusty northwest flow continues today with Small Craft
Advisories in effect for all the near shore waters. Wind gusts
of 20 to 25 kts are expected. Waves will be 1 to 3 feet for the
North Shore, and 3 to 5 feet for the South Shore and Apostle
Islands today. Winds and waves will slowly decrease this
evening. Did extend the Small Craft Advisory for the Outer
Apostle Islands, and Port Wing to Sand Island until 1 am CDT
Monday as waves will take longer to subside for these zones on
the South Shore. Elsewhere, the Small Craft Advisory is in
effect until 7 pm CDT this evening. On Monday, sunny skies,
northwest winds around 5-10kts and waves less than 1 foot are
expected.

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

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...Frost Advisory from 2 AM to 8 AM CDT Monday for MNZ010>012-019.
WI...None.
MARINE...Small Craft Advisory until 7 PM CDT this evening for LSZ121-
     140>145-147-148.
     Small Craft Advisory until 1 AM CDT Monday for LSZ146-150.

&&

$$

DISCUSSION...PA
AVIATION...PA
MARINE...PA