509
FXUS63 KDLH 190643
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
143 AM CDT Sun Jul 19 2026

.KEY MESSAGES...

- Areas of smoky conditions continue through the weekend, although
  not as widespread as the previous couple of days.

- Rain and storm chances return Sunday with the best chances
  being Sunday night into Monday. Strong to severe storms will
  be possible.

- Strong northwest winds on Tuesday may lead to more widespread
  coverage of smoke across the Northland

&&

.UPDATE...
Issued at 143 AM CDT Sun Jul 19 2026

High pressure was leading to mainly clear skies across the Upper
Midwest early this morning. A few isolated showers were seen on
radar across north-central Minnesota, but this activity was
decaying as it entered the Northland. Areas of smoke were
evident across northwest Wisconsin and along the North Shore,
leading to reduced visibilities. Warm temperatures are expected
today with highs in the 80s and lower 90s. With a Moderate Heat
Risk over most of the area along with Wet Bulb Globe
Temperatures reaching into the lower 80s, a Heat Advisory has
been issued for most of the Northland. Did not include the
southern Lake zone, but Heat Advisory conditions will be seen
from Knife River to Two Harbors with slightly cooler conditions
east of Two Harbors.

In terms of chances for showers and thunderstorms later today,
CAMs have been keying in on a cluster of storms developing this
afternoon across northwestern Ontario and then moving southeast
late this afternoon across the Arrowhead then across Lake
Superior. Additional storms will be possible across the
Arrowhead behind this cluster through the remainder of the
evening. Additional storms will then be possible through the
overnight hours. Any of these storms through the day and
overnight may be strong to severe with damaging wind gusts to 60
mph and large hail being the primary threats. A Marginal Risk
for severe storms from the SPC is in place across the entire
Northland for today. Little changes to the forecast for Monday
and beyond with another round of strong to severe storms
expected Monday ahead of a cold front with all modes of severe
weather possible.

&&

.DISCUSSION...
Issued at 150 PM CDT Sat Jul 18 2026

Today:

Some lingering smoke in the morning hours will be possible across NW
WI, the Twin Ports and the Arrowhead. Southwest to westerly winds
will begin to stream across the region as high pressure scoots to
the east. Smoke and air quality conditions will improve through the
afternoon.

An upper level ridge will be in place over the region but an
embedded shortwave is expected to ride along its edge and could
produce some light rain showers (20% chance) across the
International Border in the afternoon. The better chances for
precipitation look to arrive in the overnight hours via an
occluded system traversing across Manitoba and into Ontario.
Placement and exact timing of the bands of precipitation remain
contested when comparing the available high res guidance. Warm
sector precipitation can always get tricky with where the best
forcing of ascent will line up. Most of the guidance seems to be
keying in on a strong shortwave that ejects out of the Northern
Plains ahead of an upper level jet. MUCAPE in excess of 1000
J/kg with an EML will help to grow some elevated storms with
damaging winds and large hail being the primary threat Sunday
night into Monday morning.

Monday/Tuesday:

Continued shower and storm chances for Monday as the low pressure
system in Canada meanders to the southeast. It`s associated
cold front will also slide through the region leading to a wind
shift from out of the southwest to out of the west. Pending
placement of the cold front we will see strong to severe storms
develop once again. The convective parameter space looks
increasingly favorable for Monday with high MLCAPE and strong
upper level shear available for supercell growth. Increased low
level helicity may also support a tornado threat to go along
with the hail and damaging winds. SPC has a marginal risk (1/5)
for MN and a slight risk (2/5) for NW WI.

Tuesday should be a dry forecast but an increasing pressure gradient
over the region will lead to strong northerly winds. This may
lead to another round of widespread Air Quality Alerts as smoke
plumes from the wildfires could engulf the region once again.

Midweek

Winds weaken on Wednesday as high pressure moves over the region.
Next chances for precipitation arrive on Thursday behind the
departure of the high pressure. Not a lot of consistency among the
suite of 12Z deterministic guidance but there are signals for a
few ridge runners within our northwest flow to spawn some rain.
For now we are carrying PoPs of 20-30% through Friday with
Friday having more widespread coverage.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1230 AM CDT Sun Jul 19 2026

VFR conditions will prevail across northeastern Minnesota
through the period with MVFR visibilities across northwest
Wisconsin early this morning due to smoke. DLH will see some of
this smoke as well, but VSBYs are expected to remain VFR. Smoke
moves out after sunrise this morning with VFR conditions through
the remainder of the period. There is a low chance for an
isolated shower or thunderstorm at INL late in the period, but
confidence on timing and coverage is low. Better chances for INL
and perhaps HOB and DLH will arrive after 06z Monday.

&&

.MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 143 AM CDT Sun Jul 19 2026

Winds will be southwesterly today at 5 to 15 knots, highest near
the Twin Ports and near Grand Portage. Winds then go light and
variable tonight before increasing Monday from the southwest at
5 to 15 knots with gusts to 20 to 25 knots in the western arm of
the lake and along the North Shore from Grand Portage to Grand
Marais. A cold front then move across western Lake Superior
Monday afternoon and turns winds northwesterly, still at 5 to 15
knots with gusts to 20 to 25 knots in the western arm and along
parts of the North Shore. Conditions hazardous to small craft
will be possible Monday and Monday night. Thunderstorms may move
across the lake later this afternoon into this evening with
additional storms late tonight and again on Monday. Smoke along
the North Shore east of Taconite Harbor and along the South
Shore east of the Bayfield Peninsula may lead to visibility
reductions at times today into tonight.

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

&&

.FIRE WEATHER...
Issued at 143 AM CDT Sun Jul 19 2026

Warm and dry conditions will prevail today with highs in the 80s
and lower 90s with afternoon RH values falling into the 35 to
45% range over most of the region. Winds will be southwesterly
at 5 to 15 mph. Chances for showers and thunderstorms will be
seen this evening and overnight. Some of the storms overnight
may be strong to severe with damaging winds and large hail as
the main threats. Monday will see highs in the 80s with
afternoon RH values generally around 40% and higher. Additional
showers and thunderstorms will be possible with strong to severe
storms possible across the Minnesota Arrowhead into northwest
Wisconsin. All modes of severe weather will be possible Monday
afternoon before changing to a mainly damaging wind threat
Monday evening. Rainfall amounts will be around a tenth to 0.35
inches with heavier amounts in excess of an inch possible in
thunderstorms. Winds Monday will be southwesterly at 5 to 15 mph
with gusts to 20 to 25 mph. A cold front will move through
during the late afternoon and early evening turning winds
northwesterly behind it. These northwesterly winds will continue
for Tuesday with gusts to 25 mph.

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

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...Heat Advisory from 11 AM this morning to 8 PM CDT this evening
     for MNZ010>012-018-019-025-026-033>038.
WI...Heat Advisory from 11 AM this morning to 8 PM CDT this evening
     for WIZ001>003-006>008.
MARINE...None.

&&

$$

UPDATE...BJH
DISCUSSION...Britt
AVIATION...BJH
MARINE...BJH
FIRE WEATHER...BJH