392
FXUS63 KDLH 230654
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
154 AM CDT Thu Jul 23 2026

.KEY MESSAGES...

- Drier with seasonable temperatures today, then gradually
  warming up again and becoming hot this weekend. Heat
  Advisories may be needed for portions of the Northland
  Saturday through Monday.

- Breezy winds, fairly low relative humidity, and hot conditions
  could lead to elevated fire weather conditions for portions of
  the area on Friday through this weekend.

- A cold front Friday afternoon and night brings our best
  chance for thunderstorms, with a sliver of a slight (level 2
  out of 5), severe threat in north-central Minnesota, mainly
  for large hail.

&&

.DISCUSSION...
Issued at 151 AM CDT Thu Jul 23 2026

Generally quiet weather is affecting the Northland early this
morning, with high pressure centered over southern Minnesota. We
have light west to southwest winds, and mostly clear skies
across the area. Some storms that developed earlier this evening
over northwest Ontario where instability and shear were
sufficient for storm development have been drifting southeast
towards the Arrowhead. However, as the environment is much less
favorable here, they have been weakening to little more than
showers as they cross the border. As we head through today,
expect mostly sunny skies and seasonable temperatures climbing
into the low to mid 80s. This afternoon and evening we will get
additional shower and storm development over northwest Ontario
which may drift into the Borderlands. Have kept some small
precipitation chances going for these storms through the
afternoon and evening. Light winds will gradually turn to the
southwest and increase a bit by the afternoon. The overnight
hours tonight will be quiet and mostly clear with comfortable
lows in the upper 50s and lower 60s.

Friday afternoon and night marks our best chance at showers and
thunderstorms through this forecast period. A shortwave will
move across the flattened ridge over the western CONUS and
across the Northland Friday night. Ahead of it, southerly flow
will push in a noticeably warmer and more humid airmass, pushing
highs into the mid to upper 80s. A cold front which accompanies
the shortwave will approach from the northwest late Friday
afternoon into Friday night. Instability and shear profiles
ahead of the front suggest a few elevated supercells could
develop across northwest and north central Minnesota late
Friday. These storms will carry a level two out of five risk for
severe weather, with large hail up to ping pong ball size and
isolated damaging wind gusts being the primary hazards.

Behind the departing front on Saturday, the predominant weather
concern shifts to heat. The upper ridge will amplify and shift
east, allowing temperatures to soar into the upper 80s and low
to mid 90s. With dew points remaining elevated, heat index
values will climb into the 90s. If this trend holds, Heat
Advisories may be needed for portions of the Northland Saturday
through Monday. Precipitation chances diminish for Saturday, but
then a mid level baroclinic zone and convergence draped across
the area may bring showers and thunderstorms to the area Sunday
and Sunday night. These precipitation chances are somewhat
conditional, as warm temperatures aloft may suppress any
widespread convection.

The unseasonably hot and humid conditions will persist into
early next week, with Monday likely seeing another day of
widespread upper 80s and low 90s across the area. A slight
chance of showers and thunderstorms will linger Monday into
Tuesday, but confidence remains low on exact timing and coverage
as most of the region remains capped under the strong upper
level ridge and warm temperatures aloft. By the middle of next
week, the pattern suggests a slight moderation in temperatures
back toward the 80s, but overall conditions are expected to
remain warmer than normal for late July with relatively sparse
precipitation.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1227 AM CDT Thu Jul 23 2026

VFR conditions are expected overnight tonight. Some smoke begins
to work back into the region from the west starting tonight, but
no reductions in visibility are expected. Another day of VFR
conditions with diurnally driven cumulus expected for Thursday.
There is a 10-20% chance for a few showers and storms Thursday
afternoon near KINL and far northern Minnesota near the
International Border. Light and variable to calm southwest winds
expected overnight, but then increase out of the southwest
during the morning with daytime gusts of 14-18 kt, strongest in
the afternoon in northern Minnesota. Winds diminish once again
in the 00-02z time range.

&&

.MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 151 AM CDT Thu Jul 23 2026

Southwest winds will increase once again today to 15 to 25
knots, particularly along the North Shore and around the Apostle
Islands. Waves will build to 3 to 5 feet along the North Shore
north of Grand Marais. Another Small Craft Advisory has been
issued for these areas for today and this evening. Another round
of stronger southwest winds is anticipated for Friday into early
Saturday ahead of an approaching cold front. This is likely to
bring building waves and potentially hazardous conditions for
Small Craft.

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

&&

.FIRE WEATHER...
Issued at 222 PM CDT Wed Jul 22 2026

High pressure the rest of today and tonight keeps conditions
rain-free conditions with afternoon highs in the 70s and minimum
RH values of 30 to 40% along with partly to mostly cloudy skies
with mixing heights of 5000-7000 ft. RH recovers to 80-95%
across most of the Northland tonight.

There is a 10-20% chance for isolated showers Thursday morning
in far northern Minnesota near the International Border and a
20-30% chance for a few showers and general thunderstorms in the
same area Thursday afternoon and evening. Precipitation amounts
will be 0.10 inches or less, though very localized amounts to
0.25" cannot be ruled out for anywhere that a thunderstorm moves
overhead. Minimum RH on Thursday again dips to 30 to 40%
along with high temperatures in the low to mid 80s and southwest
winds of 5-10 mph with daytime gusts of 15-20 mph. RH recovers
above 75-80% again Thursday night.

A cold front late Friday into early Saturday brings better
precipitation chances (30-90%, highest along and north of the
Iron Range). Forecast rainfall amounts with these
scattered showers and thunderstorms are mostly 0.2-0.5" north of
the Iron Range, 0.1-0.2" for the Iron Range, and 0.1" or less
south of the Iron Range. The probabilities for localized amounts
>0.5" are only 20-40% in far northern Minnesota. Portions of
north-central Minnesota could also see a few strong to severe
storms with large hail and frequent lightning late Friday and
Friday night. Otherwise, no significant rain chances are
expected through this weekend into early next week. Temperatures
warm back into the 80s and 90s for the weekend into Monday with
breezy conditions possible both Friday and Saturday that, when
combined with the heat and fairly low RH of 35-45% for much of
the Northland, could bring about a return of elevated fire
weather conditions.

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 10 AM this morning to 10 PM CDT this
     evening for LSZ140-141.
     Small Craft Advisory from 10 AM this morning to 4 PM CDT this
     afternoon for LSZ142-143-146-147-150.

&&

$$

DISCUSSION...LE
AVIATION...LE
MARINE...LE
FIRE WEATHER...Rothstein