523
FXUS63 KDLH 071204
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
704 AM CDT Mon Sep 7 2026

.KEY MESSAGES...

- Scattered showers and thunderstorms continue across the area
  this morning. After a break in activity, additional showers
  and storms arrive this afternoon and evening. Several rounds
  of convection are possible through Tuesday.

- Marginal risk of severe storms late today into Tuesday
  morning. There remains potential for redevelopment of strong
  to severe storms Tuesday afternoon as well.

- Strong northwest winds are expected Wednesday, both inland and
  over the waters of western Lake Superior. Wind gusts to 35 mph
  are possible over the Arrowhead, with gale- force wind gusts
  over western Lake Superior this week.

&&

.UPDATE...
Issued at 330 AM CDT Mon Sep 7 2026

An area of showers and thunderstorms is moving eastward this
morning, now over the Arrowhead stretching southward to the
South Shore. Strong to severe storms are not expected given weak
shear profiles, but a wind gust to 20-25 mph and brief heavy
rainfall is possible. This activity is being driven by a weak
shortwave rounding the ridge axis that extends northward through
the Upper Mississippi River Valley that is pushing eastward
toward the Great Lakes. As that shortwave pulls to the east, a
break in rainfall is expected this morning, with cloudy skies
persisting.

As noted in the previous discussion below, we will remain in the
warm sector today, ahead of an approaching cold front
associated with a low moving into central Canada. This might
result in ongoing scattered showers, but do not expect
continuous rainfall today. The next round of organized showers
and storms arrives late this afternoon into the early evening,
from the west. This would be the first in a several of waves of
storms that will move through the area through Tuesday morning.
The evening activity might pose a severe threat with shear
values of 40kts. However, instabilities are weak, which could
limit the overall severe threat. Better lapse rates arrive early
Tuesday morning, along with weak CAPE values and bulk shear of
50kts. Could see a strengthening of storms with large hail and
damaging winds possible late tonight into early Tuesday.

As the cold front moves through the area Tuesday afternoon, a
few storms are possible mainly over the Arrowhead. If the storms
develop in the wake of widespread morning storms, they could be
strong to severe as well. Northwesterly flow will increase
behind the cold front on Wednesday, resulting in gusty winds
over the area. There is about a 40% chance of wind gusts over
40mph over the Arrowhead and parts of the South Shore, and wind
advisories might be needed.

&&

.DISCUSSION...
Issued at 231 PM CDT Sun Sep 6 2026

Tonight/Labor Day.

Overnight, the ridge axis shifts further east towards the Great
Lakes as a shortwave advances out of the Northern Plains.
Moisture profiles begin to saturate leading to a slight increase
in PoPs for the overnight and early morning hours across
northern MN. A few thunderstorms will be possible as well, but
the environment is lacking deep layer shear which will keep
storms on the tame side. Through the remainder of the holiday
the Northland will find itself in the warm sector of an
approaching system in the Northern Rockies. The continued warm
air advection and isentropic forcing may lead to off and on rain
chances through the day with mostly cloudy skies. Temperatures
will be in the 70s with a few low 80s possible. Additionally,
the southerly winds will see our dew points climb into the upper
60s by the afternoon.

Late Labor Day into Tuesday:

Large scale ascent is expected to increase late Labor Day and
through Tuesday morning. An upper level trough over the Canadian
Prairies pushes the ridge completely out of the Northland opening the
door for southwesterly flow to stream back into the region. One of
the unique aspects of this incoming set up is the high PWATs that
the system will have access to. The IVT plots would suggest
contributions from both the the Gulf and Hurricane Marie.
Climatology puts the incoming PWATs near the max of climatology.
Despite this wealth of moisture, most of the guidance keeps QPF
fairly moderated. EFI is mainly honing in on areas north of the
International Border as being the hotpots for heavy rainfall,
likely coinciding with the warm frontal boundary. While we may
not be the recipients of the highest rain totals we should still
see our fair share with current guidance suggesting around an
1" for most of MN with lower amounts across the Arrowhead and NW
WI.

Severe chances start to increase late Monday as well with an upper
level jet nudging in from the southwest. Instability may be limited
with high PWATs and lack of mid level lapse rates. With these meager
ingredients in play the SPC has out western counties outlined in a
marginal risk (threat level 1 out of 5). Primary hazard would likely
be hail the size of quarters with damaging winds being a secondary
threat. Storm activity could be persistent into Tuesday as a low
level jet strengthens across the Midwest.

Tuesday will see ongoing showers and storms through the morning. The
upper level low over the Canadian Prairies will strengthen with a
noticeable dry slot sweeping in behind the cold front set to move
through the region. Depending on how quickly the front advances
east the region we could have some lingering severe storm
threat into NW WI in the afternoon.

Wed - Fri:

On Wednesday the upper level low spins into the Hudson Bay with
persistent cyclonic flow aloft over the region. Low level moisture
still looks favorable with mid and upper level moisture questionable
at the moment. The pattern looks pretty similar to the ones we get
with isolated showers and more widespread drizzle. Overall,
expecting a cloudy day with much cooler temperatures. Highs may not
climb out of the 70s in northern MN with NW WI in the mid and low
70s. Thursday looks to be the quietest weather day in the upcoming
week with surface high pressure gliding across the Midwest. Rain
chances look to return Friday as another front cross through the
Northland.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 704 AM CDT Mon Sep 7 2026

Showers are moving through the Arrowhead this morning, with no
current rain impacts to forecast terminals. Southeast winds at
the head of the lake have allowed for low clouds and locally
dense fog to develop from KCOQ to KDLH. Low clouds are spreading
further inland, and will need to watch for cigs below 500ft at
HIB over the next hour. These conditions should improve quickly
with sunrise and mixing. Elsewhere conditions are VFR with a
mix of mid and high level clouds.

Winds will increase from the southeast through the day, with
gusts to 20-25kts this afternoon. Additional showers and storms
are expected to move into the area from the west by late
afternoon, with convection spreading eastward tonight. Storms
will bring lightning, strong gusty winds, and MVFR cigs.

&&

.MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 330 AM CDT Mon Sep 7 2026

Easterly winds continue across Lake Superior around 5 to 10
kts this morning. Winds will increase through the day, with a
few gusts to 25kts possible along the North Shore this evening.
Winds will slowly turn to out of the south this evening, and
increase further along the North Shore. By early Tuesday
morning, widespread wind gusts of 25kts are possible, with gales
possible from Grand Portage to Grand Marais. The Gale threat
diminishes Tuesday afternoon but will likely still need a Small
Craft Advisory. Widespread Gales across all the Near Shore
waters and possible the South Shore continue to look likely for
Wednesday. Additionally, showers and thunderstorms will be
possible late Monday through Tuesday evening.

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

&&

.FIRE WEATHER...
Issued at 330 AM CDT Mon Sep 7 2026

Low fire weather concerns through most of the forecast. Active
weather pattern with high dew points back across the region through
midweek. Additional rain totals for today through Tuesday night
range from around an 1" across northern MN with less amounts
expected south of US-2 eastward into NW WI. The heaviest
rainfall is expected tonight into Tuesday morning. Additionally,
there will be the risk of strong to severe storms tonight into
Tuesday morning, with an isolated risk of a strong to severe
storm again Tuesday afternoon.

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 from 4 AM Tuesday to 7 AM CDT Wednesday
     for LSZ121-142>148-150.
     Small Craft Advisory from 7 PM this evening to 4 AM CDT
     Tuesday for LSZ140.
     Gale Watch from late tonight through Tuesday afternoon for
     LSZ140.
     Small Craft Advisory from 7 PM this evening to 7 AM CDT
     Wednesday for LSZ141.

&&

$$

DISCUSSION...Britt
AVIATION...HA
MARINE...HA
FIRE WEATHER...HA