Duluth, Minnesota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

241
FXUS63 KDLH 260637
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
137 AM CDT Sun Jul 26 2026

.KEY MESSAGES...

- Dense fog this morning creates very low visibilities for those
  traveling.

- Hot conditions are expected Sunday, with Heat Advisories and
  Extreme Heat Warnings in effect.

- Conditional threats for severe thunderstorms through Monday
  morning. If thunderstorms develop, isolated to scattered
  severe storms are likely, capable of producing damaging winds,
  large hail, and frequent lightning.

- Warm temperatures continue through the coming week, with
  occasional precipitation chances.

&&

.UPDATE...
Issued at 138 AM CDT Sun Jul 26 2026

Infrared satellite imagery early this Sunday morning shows the
expanding areal coverage of dense for for inland north-central
Wisconsin over the last hour. Surface observation stations show
visibilities around or less than one quarter mile for eastern
Sawyer County and Price County...further supported by webcam
imagery in Park Falls. A Dense Fog Advisory was issued and runs
through 9 AM for these two counties given these conditions.
Scattered dense fog observations are also ongoing in northeast
Minnesota presently. High res model guidance indicates these
conditions expand in areal coverage over the next few
hours....which may necessitate further areal expansion of the
land-based Dense Fog Advisory to the I-35 corridor into Leech
Lake and northward along the Iron Range.

Other locations immediately along the Lake Superior shorelines
could also have a brief period of marine dense fog move onshore,
mainly for the tip of the Bayfield Peninsula.

Hazy skies are expected today from western U.S. wildfire smoke
aloft moving in from the west-northwest late morning to this
afternoon. High-res model guidance limits most of the smoke to
aloft, but very limited concentrations could be lightly smelled
at the surface today. For this case, Smoke was added into the
Weather forecast this afternoon into the Monday daytime time
period.

Very hot conditions remain expected today for areas south of
the Iron Range and Leech Lake south into the Brainerd Lakes
region in northern Minnesota, and across almost all of northwest
Wisconsin. Heat Indices of 95 to 105 degrees F are forecast.
The Heat Advisories and Extreme Heat Warnings remain in effect
today.

The conditional threat of scattered severe thunderstorms
occurring late afternoon today through the overnight hours
tonight remains the case for the morning forecast today. Even
though the wind begins late this afternoon, the most likely time
period for any severe weather today would be mostly favored
mid-evening to early overnight hours tonight for a large hail
threat, then followed later this evening into the overnight
hours for a damaging winds threat. Wind gusts in excess of 70
mph would be possible tonight if the predominant storm mode is
able to become clustered. The high uncertainty in the cap
actually breaking across much of the region keeps the Chance of
Precip forecast limited to a 60% chance at this time, even with
high resolution model blends favoring higher chances for the
overnight hours tonight.


&&

.DISCUSSION...
Issued at 214 PM CDT Sat Jul 25 2026

Clouds are clearing this afternoon under west to northwesterly flow,
with a hot and humid day developing. Temperatures should jump up
quickly with sunnier skies, pushing high temperatures into the 80s
to near 90F with moist dewpoints. A Heat Advisory remains in effect
for portions of the area through this evening.

As an upper level high pushes east overnight, a weak upper level
disturbance along its periphery along with a marginal LLJ could
force a couple storms out of a well-capped and somewhat dry air mass
along the International Border and into the MN Arrowhead. The
primary issue here is the actual development of storms, if that can
occur, decent MUCAPE and ample bulk shear should allow for storms to
grow into a respectable elevated storm severe threat, with damaging
winds and large hail as the primary hazards. As the LLJ weans into
Sunday morning, any areas of precipitation that do develop should
weaken or diminish.

Sunday, a hot and moist airmass should push from the Dakotas into
the Northland. Widespread high temperatures in the 90s (near 100F in
the Brainerd Lakes region) combined with dew points in the upper 60s
to mid 70s will make for an uncomfortable, and at times somewhat
oppressive, heat. Heat Advisories and Extreme Heat Warnings are in
effect. With that heat and humidity, an impressive reservoir of
instability is expected to develop, with models suggesting 3000-
4000+ J/kg of MUCAPE across Minnesota, Wisconsin, and the UP. Along
with that, around 50 knots of bulk shear could combine with steep
mid level lapse rates to develop clusters of storms from the
International Border and southeastward across the aforementioned
region. With the heat we`re expecting, there will be a cap to
overcome, which seems most likely to occur in the late afternoon to
evening hours, but the potential for the cap to not break is there,
limiting our PoP forecast for now. Storms will likely be pretty
quick if they develop, cruising from northwest to southeast with a
damaging wind and large hail threat. Our entire area is in a Slight
Risk (level 2/5) for Sunday. As additional upper level shortwaves
continue to move along the edge of the high pressure, some storms
could continue to form and propagate over the MN Arrowhead into NW
WI Monday morning, where a Day 3 Marginal risk is in effect.

Monday and through the work week, temperatures temper slightly, but
are still largely expected to be around to above normal with
afternoon highs in the upper 70s to upper 80s and overnight lows in
the 50s and 60s. We remain in a somewhat stagnant pattern stuck
between an upper level high over the Southwest to Central Plains and
semi-transient upper level lows moving over central to eastern
Canada. This should continue to put us in position to see the
influence of occasional ridge running disturbances which could bring
spotty rain showers and thunderstorms. Some global models are
suggesting the potential for a slightly stronger upper level
shortwave to bring a more potent system to the area late in the
week, but confidence is extremely low in any solutions that far out
at this point.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1205 AM CDT Sun Jul 26 2026

LIFR to MVFR fog sets up tonight at most terminals with these
conditions likely to be mixed with a few observations of VFR
as the fog temporarily moves away. Expect these conditions
through 11-13Z this morning before VFR conditions setup. MVFR
ceilings slowly burn off towards the 14-16Z though this morning.
Incoming band of western U.S. wildfire smoke aloft creates hazy
skies so went with BKN200 in the TAFs for those likely
conditions. If any smoke mixes down though, high-end MVFR
conditions cannot be ruled out this afternoon. Widely scattered
thunderstorms may form this afternoon and overspread northeast
Minnesota into northwest Wisconsin this evening and overnight.
Kept TAFs though to PROB30s at this point given the low-
confidence on areal extent of any possible thunderstorms still
late in this TAF period.

&&

.MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 1245 AM CDT Sun Jul 26 2026

Dense fog continues for western Lake Superior along the
nearshore this morning with Advisories in effect. Even as the
most dense fog drops south of the far North Shore early this
morning and sets up along the South Shore, a return back towards
the Grand Marais area is possible again later today. The
current Advisories may have to be extended in time or re-issued
for nearshore waters into Sunday afternoon. After light easterly
winds today, expect an uptick in speeds Monday as a notable
lake breeze sets up. Onshore northeast flow of 10 to 15 knots
gusting to 20 knots is forecast to create waves around 2 feet
Monday.

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

&&

.FIRE WEATHER...
Issued at 1240 AM CDT Sun Jul 26 2026

The main hazard forecast for fire weather these next few days
would be strong to isolated severe thunderstorms, most likely
this evening into tonight. Gusty and erratic winds, cloud to
ground lightning and large hail are the primary threats from
any possible strong storms later today. Otherwise, Extreme Heat
is forecast today for districts along and south of US Hwy 2 with
Warnings in effect for that heat. Heat Advisories are also still
in effect through for all other districts too, but just less hot
conditions. West to southwest winds today shift to northerly
Monday and bring in a more moderate temperature airmass,
although lingering heat for the Brainerd Lakes. A lake breeze
off Lake Superior will occur Monday.

Smoke from western U.S. wildfires moves over the region even
more so today and is forecast to produce hazy skies, but with
limited mixing down to the surface.

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

&&

.CLIMATE...
Issued at 1235 AM CDT Sun Jul 26 2026

A few daily temperature records are forecast to be within a few
degrees of either bring tied or broken in the Northland today.

Record High Temperatures:

July 26:        Forecast
KDLH: 92/1930   90
KHIB: 91/2015   91


Record Daily Warm Low Temperature:

July 26:        Forecast
KBRD: 72/189969

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...Heat Advisory from 11 AM this morning to 9 PM CDT this evening
     for MNZ010>012-019>021.
     Extreme Heat Warning from 11 AM this morning to 9 PM CDT this
     evening for MNZ018-025-026-033>038.
WI...Heat Advisory from 11 AM this morning to 9 PM CDT this evening
     for WIZ004-009.
     Extreme Heat Warning from 11 AM this morning to 9 PM CDT this
     evening for WIZ001>003-006>008.
     Dense Fog Advisory until 9 AM CDT this morning for WIZ008-009.
MARINE...Dense Fog Advisory until 10 AM CDT this morning for LSZ142-143-
     146-147-150.
     Heat Advisory from 11 AM this morning to 9 PM CDT this evening
     for LSZ142.

&&

$$

UPDATE...NLy
DISCUSSION...Levens
AVIATION...NLy
MARINE...NLy
FIRE WEATHER...NLy
CLIMATE...NLy