271
FXUS63 KDLH 040546
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1246 AM CDT Thu Sep 4 2025

.KEY MESSAGES...

- Frost potential tonight for most areas.

- Light rain and snow showers possible tonight.

- Widespread rain along and south of US-2 Thursday into Thursday
  night.

- Cool temperatures to end the week, then a gradual warm up
  into next week.

&&

.DISCUSSION...
Issued at 244 PM CDT Wed Sep 3 2025

This Afternoon:
Plenty of clouds are hanging around this afternoon under
cool cyclonic flow aloft. It`s feeling like fall out there with
current temperatures in the 50s and even staying in the 40s in
the tip of the Arrowhead. There are some widely scattered
showers out there as well, and that activity is generally
expected to persist into tonight.

Tonight:
Plenty of weak synoptic lift will prevail tonight, and while
there is likely to be at least partial clearing, there should be
at least some clouds and a few showers hanging around through
the night. The best chance for clouds and a few showers will be
across the Arrowhead, closer to the best synoptic forcing
associated with the low up in Ontario. It does look like there
has been a slightly drier trend with this update, so whether or
not the first snowflakes of the season will actually fall in the
Arrowhead early Thursday morning is still in question, but the
possibility still remains.

Regarding frost potential tonight, we decided to go with a
fairly broad frost advisory. This is a low confidence setup for
frost given that we will have clouds hanging around with some
uncertainty about how much clearing we will actually have as
well as a fairly tight pressure gradient that will keep the
winds from calming down. Therefore, it`s not an ideal
radiational cooling night. With that said, the cool air mass
should easily result in air temperatures falling below 36
degrees for many, if not most places, and areas that see some
peeks of clearing and perhaps some decreasing winds (even if
they don`t become calm) could easily see some frost. It`s one of
those kinds of nights where not everyone will see frost, but
it`s tricky exactly to tell where exactly it will happen, and
the potential is there for many places. Therefore, coverage of
frost advisories is pretty broad, only excluding the North Shore
coastlines and around Brainerd to Hinckley where temperatures
should remain a bit warmer.

Thursday through Saturday:
A quick-moving clipper system is expected to pass through and
bring a swath of rain mainly along and south of US-2 Thursday
into Thursday night. Totals up to around a quarter to half an
inch on the high end. As we go into Friday, the cool cyclonic
flow continues with a tight pressure gradient resulting in some
20-30 mph wind gusts. Scattered showers are expected to linger
in some places with lingering moisture. Saturday is looking like
nearly a repeat of Friday, just with slightly warmer
temperatures.

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 /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1247 AM CDT Thu Sep 4 2025

Very isolated, intermittent rain showers persist during the
current overnight, but decrease in coverage towards this
morning. Winds remain west-northwesterly to westerly into most
of Thursday, with winds picking up mid to late morning into
afternoon with gusts of 14-18 kt for most areas. Better
potential for more widespread rain showers return to the area
from the west by mid to late afternoon and persist through at
least the end of the current TAF period, though INL may be more
on the fringe for showers. Conditions should deteriorate with
the showers, as well, with MVFR conditions for KHIB/KDLH and
terminals south in the evening and potentially IFR ceilings at
KBRD/KHYR after 03Z on Thursday evening.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 244 PM CDT Wed Sep 3 2025

Blustery northwest winds have arrived, though gusts this
afternoon have been a little bit less than anticipated. But,
gusts have hovered in and around 20-25 kt for many places, and
that is expected to persist tonight through Thursday afternoon
before tapering off a bit into Thursday night briefly. Winds
pick up again on Friday as a clipper system passes through, so
expect more 20-30 kt wind gusts that will be hazardous for small
craft through Friday evening. Winds gradually decrease going
into Saturday.Occasional rain showers can be expected through
Saturday.

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

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...Frost Advisory until 8 AM CDT this morning for MNZ010>012-018-
     019-025-026-035-037.
WI...Frost Advisory until 8 AM CDT this morning for WIZ001>004-
     007>009.
MARINE...Small Craft Advisory until 5 PM CDT this afternoon for LSZ121-
     140>148-150.

&&

$$

DISCUSSION...JDS
AVIATION...Rothstein
MARINE...JDS