387
FXUS63 KDLH 091132
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
632 AM CDT Wed Jul 9 2025

.KEY MESSAGES...

- High pressure builds in today with quiet weather.

- Slight chances for showers and storms early Thursday, but best
  chances are late Thursday/Friday. Best chances for severe
  weather will also be late Thursday/Friday.

- Showers and storms may linger into the weekend, though models
  differ. More chances for showers and storms early next week.

&&

.DISCUSSION...
Issued at 211 AM CDT Wed Jul 9 2025

Fog and low stratus off Lake Superior is creating dense fog
along portions of the South Shore. As the sun rises and the
surface starts to mix out, the fog should slowly dissipate
throughout the morning. Once the fog clears, high pressure
currently over the region will lead to a quiet weather day.
However, skies may be milky in the morning due to wildfire smoke
aloft.

A ridge will move across the Northern Plains tonight into
Thursday, and the WAA combined with small shortwaves along the
ridge may lead to scattered thunderstorms across north central
Minnesota, but CAMs are still in disagreement of whether storms
will initiate this far north due to capping in the mid levels.
Better chances for storms will be Thursday afternoon and evening
as the cap erodes from surface diurnal heating. CAMs differ on
when the cap erodes, however, so timing is uncertain.
Instability is plentiful throughout Thursday afternoon and
evening, though wind shear is modest, at 15-25 kts across the
CWA. Storm mode will when likely be stationary up-and-down
cells, with main hazards being hail and damaging winds. However,
model soundings are hinting at a limited threat for hail from
high moisture throughout the hail growth zone which points to
a more heavy rain signature. PWATs 1.5-2" across the area could
lead to localized flooding, especially if storms train over the
same area.

A cold front will move through the Northland starting Friday
morning and will move southeast throughout the day. Otherwise
the environment will largely remain the same with plenty of
instability and weak shear. PWATs will remain high, the threat
for localized flooding continuing.

Timing of the departure of the cold front differs among global
models, and showers and storms may continue into Saturday,
particularly in northwest Wisconsin. Once it passes, a ridge
builds in for most of Sunday before chances for showers and
storms return early next week. Timing is uncertain with
discrepancy in the models.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 627 AM CDT Wed Jul 9 2025

Fog and stratus is starting to lift, but have TEMPOs in place
for occasional dips in conditions for the next couple hours. VFR
conditions will then prevail for the rest of the TAF period.
There is a slight chance for some showers and storms at INL
tonight, but probabilities are too low (10%) to include in the
TAF.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 211 AM CDT Wed Jul 9 2025

Dense marine fog along the South Shore will persist into the
morning, with visibilities as low as a quarter mile in some
areas. Northeast winds at the head of the lake will continue
and increase this afternoon, with gusts up to 15 kts and waves
1-2 ft expected. Lighter winds will be present across the rest
of the near shore waters. Winds and waves will increase further
for Thursday afternoon due to an approaching low pressure
system. Strong thunderstorms are possible Thursday night through
Friday.

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

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...Dense Fog Advisory until 9 AM CDT this morning for WIZ002>004.
MARINE...Dense Fog Advisory until 10 AM CDT this morning for LSZ121-147-
     148.

&&

$$

DISCUSSION...KML
AVIATION...KML
MARINE...KML