399
FXUS63 KDLH 080807
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
307 AM CDT Tue Sep 8 2026

.KEY MESSAGES...

- Widespread showers and thunderstorms continue this morning. A
  few storms may become strong, capable of producing wind gusts
  of 40mph, small hail, and very heavy rainfall.

- Strong west-northwest winds are very likely on Wednesday, with
  gusts of 30 to 40 mph forecast. Winds are most likely to be
  strongest in the Minnesota Arrowhead.

- Additional precipitation chances arrive late this week into
  the weekend. A pattern change to cooler temperatures is
  favored this weekend into early next week.

&&

.DISCUSSION...
Issued at 144 AM CDT Tue Sep 8 2026

A warm front extending from a surface low centered over south
central Canada stretches west to east just north of the Canadian
border this morning, with dewpoints in the 60s across the
Northland. A cold front extends southward from that surface low
through the Plains. Ahead of the cold front, southerly flow
continues to bring moisture northward. In response to a
strengthening LLJ, clusters of showers and storms developed
overnight and are moving northeastward, generally south of the
US-2 corridor in north central MN and now approaching the Twin
Ports and moving into northwest WI. Additional showers have
developed across the Arrowhead. Despite PWs around 1.8 inches
and locally heavy rainfall under the stronger storms, activity
is transient and has not presented a flooding threat. There is
sufficient MUCAPE for updrafts, but given relatively warm,
saturated profiles and weak lapse rates, do not expect severe
storms overnight. The ongoing storms will continue
northeastward, likely still impacting the I-35 corridor and Twin
Ports during the morning commute.

In it`s wake, cloud cover will linger through the morning, but
with the cold front still to our west, there is a chance of
continued scattered showers. The front moves through the region
this afternoon, and CAMs suggest a few storms could develop
along that boundary. Lapse rates will be better with 50kts of
bulk shear overlapping a nose of 500-1000 J/kg of CAPE
(depending on model of choice) just ahead of the front. With
widespread cloud cover, it could be difficult to realize that
instability. If storms can develop, there could be strong storm
or two.

Following the cold frontal passage, a more benign pattern
settles over the CWA around mid-week as high pressure builds.
Ahead of this high pressure, west-northwest winds are very
likely to become strong during the daytime hours on Wednesday.
Wind gusts of 30-40 mph are forecast, strongest in the
Arrowhead. A few gusts in excess of 40 mph are not totally out
of the question, although the NBM probability for inland
locations along the North Shore is a low 10-20%. Wind Advisories
may be needed on Wednesday, especially if winds show an
increasing trend.

The next chance for precipitation arrives late into the week into
the weekend as additional troughs potentially propagate through the
CWA. One upcoming pattern change of note is a temperature change
arriving this weekend into early next week. While high temps most of
this workweek will be in the 70s for most, high temps by this
weekend into early next week will likely be in the 60s (with a few
upper 50s not out of the question!).

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 112 AM CDT Tue Sep 8 2026

Clusters of showers and storms are moving through the Northland
this morning, with potential impacts at all terminals through
early Tuesday morning. Stronger storms could produce wind gusts
to 35kts, frequent lightning, and heavy rainfall. Have timed
out impacts based on current radar trends. There could be
additional development before 12Z, with coverage expanding
northward over the Arrowhead.

Expect breezy south winds outside of convection, with gusts to
20-25kts. Behind convection, a period of IFR/MVFR cigs is
possible with cigs slow to lift through the morning. Winds will
shift to the southwest Tuesday afternoon, with gusts to 20-25kts
remaining possible.

There is a low chance of additional showers or storms Tuesday
afternoon as a weak cold front moves through. Chances at any
terminal are too low to include at this time.

&&

.MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 144 AM CDT Tue Sep 8 2026

Southeast to south winds increase this morning, with widespread
gusts of 25 knots or greater are expected across western Lake
Superior, with gales expected from Grand Portage to Grand
Marais. The Gale threat diminishes this afternoon, although a
Small Craft Advisory will likely be needed for these nearshore
waters. Widespread Gales continue to look likely for Wednesday
as a tight pressure gradient develops. Therefore, a Gale Watch
was issued across western Lake Superior on Wednesday.

Outside of the expected elevated winds, thunderstorms are forecast
this morning. A few storms may be strong, capable of producing
wind gusts in excess of 30 knots, small hail, and frequent
cloud- to- water lightning.

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

&&

.FIRE WEATHER...
Issued at 144 AM CDT Tue Sep 8 2026

Numerous to widespread showers and thunderstorms will continue
across portions of the Northland early this morning with most
of the activity along and south of US-2 in north central MN,
expanding into the Arrowhead and across northwest WI. Additional
rainfall amounts around 1 inch are possible from the I-35
corridor eastward, and along portions of the North Shore. Lesser
amounts expected north of US-2 and across the Arrowhead.

Severe storms are not expected, but frequent lightning and gusty
winds to 40 mph are possible with stronger storms. Outside of
convection, strong southerly winds will gust to 25mph, turning
to the southwest this evening, and diminishing.

Strong west-northwest winds are very likely to arrive on
Wednesday, with the potential for gusts of 30-40 mph. Strongest
winds on Wednesday are most likely to be in the Arrowhead,
especially on exposed ridges. While winds will be strong,
lingering moisture will result in min RH of 40% or greater on
Wednesday afternoon. Winds ease Wednesday evening as high
pressure builds into the area.

See the Fire Weather Forecast product for a more thorough
breakdown of fire weather conditions.

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
MARINE...Small Craft Advisory until 7 AM CDT Wednesday for LSZ121-
     142>148-150.
     Gale Watch from Wednesday morning through Wednesday afternoon
     for LSZ121-140>148-150.
     Small Craft Advisory until 4 AM CDT early this morning for
     LSZ140.
     Gale Warning until 1 PM CDT this afternoon for LSZ140.
     Small Craft Advisory until 7 AM CDT Wednesday for LSZ141.

&&

$$

DISCUSSION...HA/Unruh
AVIATION...HA
MARINE...HA
FIRE WEATHER...HA