Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 221432
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
932 AM CDT Wed Jul 22 2026

.KEY MESSAGES...

- Drier with more seasonable temperatures today, then gradually
  warming up again and becoming hot next weekend.

- A few areas of storms possible for the end of the work week
  into the weekend. Some strong to severe thunderstorms are
  possible at times.

&&

.UPDATE...
Issued at 310 AM CDT Wed Jul 22 2026

High pressure builds into the Northland early this morning, bringing
fair and dry conditions across the region for today. Southwesterly
flow develops on Thursday, initiating a warming trend and
bringing a slight chance of showers and thunderstorms to far
northern areas late in the afternoon and evening. High pressure
slips to the east, allowing increased moisture into northern
areas.

An upper level disturbance and trailing cold front push across the
Upper Midwest on Friday into Friday night. This system will tap
into increasing warmth and humidity, generating a risk for strong
to severe thunderstorms late Friday afternoon into Friday night,
mainly focused across northern Minnesota. Heavy rain, large hail,
and damaging wind gusts will be the primary concerns with
storms.

&&

.DISCUSSION...
Issued at 220 PM CDT Tue Jul 21 2026

Today - Tonight:

A secondary cold front is moving southward through the Northland
this afternoon with weak cyclonic flow behind it. There is just
enough low-level moisture in this pattern to produce
intermittent sprinkles and a couple very light rain showers this
afternoon in portions of northeast Minnesota and northwest
Wisconsin, but very little to no rain accumulations are
expected. Otherwise, partly to mostly cloudy skies continue
through early evening alongside northerly to north-northwesterly
winds gusting to 20-30 mph and substantially cooler high
temperatures in the mid-60s north to mid-70s south relative to
what we have been seeing recently. Despite relatively higher
minimum relative humidity values of 40-50% this afternoon, the
stronger winds set the stage for near-critical fire weather
conditions in much of northeastern Minnesota through early
evening.

Much more comfortable low temperatures in the mid-40s to around
50 degrees settle in tonight alongside calm to light and
variable winds and clear to mostly clear skies.

Wednesday - Early Thursday:

High pressure sliding through the region on Wednesday into early
Thursday will keep the weather during this timeframe dry with
mild conditions continuing. Some scattered diurnal cumulus
develops mid/late Wednesday morning into early evening,
otherwise conditions will be mostly clear. High temperatures on
Wednesday will be seasonal in the low to upper 70s, with
Wednesday night lows in the upper 40s to mid-50s.

Late this Week - Weekend:

The upper-level pattern becomes amplified late this week into
weekend with broad mid- and upper-level ridging over the western
U.S. and a trough over eastern Canada/eastern U.S. This will set
up northwest flow over the Upper Midwest in which a few
shortwave troughs could move through the region while
temperature trends will be on the rise. The first round of
precipitation potential would be a 10-40% chance for in far
northern Minnesota--mainly north of the Iron Range--late
Thursday and Thursday evening. The better chances (30-80%,
highest across northern Minnesota) would be with another
shortwave trough and attendant surface front Friday evening into
Saturday morning. There are additional, low-end shower and storm chances
(20-40% chances) on Saturday and Sunday, but confidence is
lower as to the timing and southward extent of any shortwave
troughs rounding the top of the ridge into the Northland due to
the closer proximity of the mid/upper-level ridge axis by that
time. Depending on how quickly the cold front clears the
Northland on Saturday, there could be a brief window of time
late Saturday where an instability/shear combination could
support strong to severe storms. There is also a weak signal for
strong to severe storm potential on Sunday, but confidence in
potential and locations is low at this time. Regardless, there
is not a strong signal for widespread precipitation amounts over
the next 7 days, with probabilities of >0.25" through the
weekend ranging from 50-60% in the Iron Range and north to
30-40% in much of northeast Minnesota and northwest Wisconsin
and 20% in central Minnesota.

High temperatures gradually warm from the low to mid 80s on
Thursday to mid-80s to low 90s on Saturday and Sunday, though
onshore flow/lake breeze on Sunday would likely keep the hottest
conditions away from Lake Superior. Still, this heat would
likely lead to Heat Advisory for portions of the Northland this
weekend. These hotter conditions combined with fairly low
relative humidity and breezy conditions at times could lead to a
return of elevated fire conditions for Friday into this weekend.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 619 AM CDT Wed Jul 22 2026

Fog has developed at HYR, and will linger over the next hour or
two before dissipating as we mix out. A stratus layer has also
developed across much of northeast Minnesota with bases around 6
kft. This cloud deck will break but diurnal cumulus will cover
much of the area with the same ceiling height. Northwest winds
up to 15 kts will decrease this evening and shift southwest
overnight before increasing once again Thursday morning.

&&

.MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 932 AM CDT Wed Jul 22 2026

Adjustments were made to the start time of the Small Craft
Advisory today. Southwest wind gusts up to 25 knots don`t begin
until around mid-afternoon, so the Small Craft Advisory for
Taconite Harbor to Grand Portage now starts at 3 PM CDT. The
remainder of the forecast is unchanged.

Previous Discussion: A Small Craft Advisory is in effect from
10 AM to 10 PM today for nearshore waters from Taconite Harbor
to Grand Portage, where southwest wind gusts up to 25 knots and
waves of 1 to 3 feet are expected. Otherwise, southwest winds of
10 to 15 knots with gusts to 20 knots will persist through
Thursday. Waves across western Lake Superior will generally
range from 1 to 3 feet, building to 2 to 4 feet near Grand
Portage Wednesday and Thursday afternoons.

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

&&

.FIRE WEATHER...
Issued at 310 AM CDT Wed Jul 22 2026

High pressure over the region will keep weather rain-free today
and Thursday. Relative humidity values will drop into the 30 to
40 percent range both afternoons. Light winds today will turn
southwesterly at 5 to 10 mph on Thursday with afternoon gusts
up to 20 mph. Heat and humidity will build Friday into the
weekend, with breezy conditions returning Friday and Saturday,
with winds up to 25 mph. The next chance for significant
rainfall will be Friday night into Saturday along the Canadian
Border into the Arrowhead with rainfall between 0.25-0.5".

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 3 PM this afternoon to 10 PM CDT
     this evening for LSZ140-141.

&&

$$

UPDATE...KML
DISCUSSION...Rothstein
AVIATION...KML
MARINE...Rothstein
FIRE WEATHER...KML