039
FXUS63 KMQT 240621
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
221 AM EDT Mon Aug 24 2026

.KEY MESSAGES...

- A Beach Hazard Statement is in effect today for the shoreline
  of Alger County due to strong winds and high waves creating
  dangerous rip currents and swimming conditions.

- Fog is possible across much of the central and eastern U.P.
  tonight.

- The next chances for widespread showers and thunderstorms
  arrives in the west on Tuesday, spreading east overnight and
  Wednesday before ending for most late Wednesday.

- Generally seasonable temperatures are expected through the
  rest of this week.

&&

.DISCUSSION...
Issued at 221 AM EDT Mon Aug 24 2026

With clear skies overhead this morning, observation stations are
already showing temperatures dropping into the 40s and even mid to
upper 30s across the western half of the U.P., with the Baraga Plains
RAWS site already down to 37F as of 1 AM EDT. Should this trend
hold, there could be multiple spots in the western interior U.P.
that see lows bottom out in the mid to potentially even lower 30s,
allowing patchy frost to form (particularly elevated sfcs). In
addition, there could be some patchy fog over the far west as warm
air advection aloft moves overhead, but confidence on fog occurrence
is still somewhat low even now given the lack of it being seen
upstream in northern WI and MN on satellite. After the sun rises
today, expect fairly calm and quiet weather as high pressure ridging
moves overhead. While we should be warmer than we were yesterday,
with antecedent cooler air taking time to move out of the area,
thinking highs will generally stay within the 70s. Gusty NW winds
over Lake Superior will keep dangerous waves and rip currents over
the beaches of Alger County today, so another Beach Hazard Statement
is in effect throughout the entirety of today over there. The
swimming conditions along the Marquette County shoreline are better
today due to the shore`s geometry protecting it somewhat from NW`rly
winds. Nevertheless, some rip currents and hazardous waves are still
expected along the beaches of Marquette County, so swimmers should
still exercise caution and not get into the water unless they are
experienced swimmers as the rip currents and waves could still tire
out people fast.

Moving into tonight, expect the generally quiet weather to continue
as clouds build in from the west with time via an approaching
Clipper low. Given the continuing WAA, lows tonight are expected to
not be as cool as they are this morning; that being said, some of
the coldest spots in the interior central and east could drop down
into the mid to upper 30s thanks to mostly clear skies for the
overnight hours. In addition, with WAA continuing in the lower to
mid-levels of the atmosphere, some fog is possible over mainly the
interior central and east tonight as temperatures cool to around the
dewpoint. Should the fog form, we could see visibilities of 1/2 mile
or less, which could create traveling/visibility concerns for the
morning commute for those going to work and/or school.

Our next shot of rainfall looks to arrive over the western U.P. on
Tuesday as the Clipper approaches. While global/medium range
guidance is more reserved on the start time of the rainfall, some of
the CAMs do show showers starting as early as the mid-to-late
morning hours over the far west given the modest isentropic lift
moving into the area. That being said, with not much diurnal
instability to work with, I have my doubts as to rain chances
starting that early. Therefore, have the precipitation chances
capped at around 30% between 8 AM and 2 PM EDT over the west half on
Tuesday. As better diurnal instability develops over the area and a
LLJ develops and brings some support by the afternoon hours, shower
and thunderstorm chances increase over the west half. While the best
shearing and helicity are projected to be south of us in northern
WI, thinking it may not be totally out of the realm of possibility
for a stronger (but sub-severe) thunderstorm or two to occur. As the
showers and storms continue and spread into the rest of the U.P.
Tuesday night and Wednesday, expect the rainfall chances to become
maximized to ~80 to 90% as the low`s center moves through Lake
Superior. The additional forcing from the low with PWATS 1.25 to
1.50 inches could bring heavy rainfall at times, although QPF
guidance is fairly muted for the most part on rain totals with this
event. Therefore, while it does seem like most, if not all, of the
U.P. will see at least some rainfall, given the convective nature of
the precipitation not everyone will see similar amounts; as of now,
the NBM currently has a 50 to 99% of a quarter inch of rainfall
occurring between Tuesday morning and Thursday morning, with the
greatest chances over the east and interior west whereas the lowest
chances are in the south central. The rainfall chances look to
generally end over the area by late Wednesday as the Clipper lifts
northeast towards James Bay. However, some CAA behind the low could
kick-off some light lake effect rain showers over the area on
Thursday, but accumulations would be very small as high pressure
builds in from the west once more.

High pressure ridging returns to the U.P. once again by Friday,
allowing for dry weather to return to the area. Moving into this
upcoming weekend there really isn`t a good signal for the
precipitation chances as some upper level ridging continues to build
into the area, even as troughing starts to move back in at the sfc
late this upcoming weekend. Nevertheless, expect the seasonable
temperatures to continue on from this week on into next week as
medium range guidance hints at a somewhat more active pattern
continuing into early September.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 104 AM EDT Mon Aug 24 2026

VFR conditions are expected through the TAF period. A surface ridge
will build over the region tonight into Monday bringing fair
weather. Winds will be mainly light except for gusts to 20kt at SAW
during the mid-morning through early afternoon as mixing increases.
A lake breeze will bring a wind shift to the northeast during the
afternoon at SAW, ending the potential for wind gusts from mixing.

&&

.MARINE...
Issued at 221 AM EDT Mon Aug 24 2026

Northwest winds of 20 to 30 knots over Lake Superior and 20 to 25
knots over northern Green Bay and northwest Lake MI slowly dwindle
to 15 knots or less by this evening as the center of high pressure
ridging finally arrives over the area. However, as a Clipper low
approaches Lake Superior on Tuesday, expect winds to pick up from
the south over Lake MI, Green Bay, and eastern Lake Superior, with
gusts of 20 to 30 knots being seen by Tuesday evening. In addition
to the winds, showers and storms begin moving over western Lake
Superior on Tuesday, continuing through the rest of the Upper Great
Lakes Tuesday night through Wednesday before generally wrapping-up
late Wednesday as the Clipper lifts towards James Bay. As this
occurs, expect the winds to slowly become westerly, first over Lake
Superior Wednesday morning before shifting westward over northern
Green Bay and northwest Lake MI by Wednesday evening. As this
occurs, expect the winds to die-down to 15 knots or less over
northern Green Bay and northwestern Lake MI, whereas westerly winds
of 20 to 25 knots continue over Lake Superior. CAA behind the
Clipper is expected to veer the winds to the northwest, keeping the
20 to 25 knot winds over at least the eastern half of Lake Superior
on Thursday as northwest winds of 15 to 20 knots develop over
northern Green Bay and northwestern Lake MI. As high pressure builds
in from the west late this week, expect the winds to die-down to 15
knots or less again by Thursday evening and to remain light into at
least this upcoming weekend if not potentially longer.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Beach Hazards Statement from 8 AM EDT this morning through
     this evening for MIZ006.

Lake Superior...
None.
Lake Michigan...
None.

&&

$$

DISCUSSION...TAP
AVIATION...NL
MARINE...TAP