822
FXUS63 KMQT 300733
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
333 AM EDT Sat Aug 30 2025

.KEY MESSAGES...

- Patchy dense fog is possible early this morning across the
  interior of Upper Michigan, particularly the interior west.

- A calm and pleasant Labor Day weekend is in store!

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 333 AM EDT Sat Aug 30 2025

The quieter and calmer weather continues today through tonight as
high pressure ridging remains overtop the area. However, some patchy
dense fog could impact the interior areas (particularly the interior
west) early this morning, dropping visibilities down to a quarter
mile or less at spots. Should this be seen via webcams and
observations, then an SPS will be forthcoming; if you end up in the
fog, be sure to have your low-beam headlights on and take any
driving a bit slower.

Once we get into the daylight hours and any fog we did have burns
off, expect another pleasant day as temperatures warm to the 70s.
While lake breezes from Lake Superior and Lake Michigan are expected
by the afternoon hours, given that the difference between the land
and lakes sfc temperatures won`t be that large, the lake breezes
should be fairly weak and struggle to get really deep inland. Moving
into tonight, no fog or frost is expected as lows will be warmer
than this morning, only dropping down into the mid 40s as warm air
advection slowly moves back over the Upper Midwest.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 333 AM EDT Sat Aug 30 2025

The latter half of the holiday weekend will be influenced by the mid
level ridge setting up over the Great Lakes with associated high
pressure strengthening at the sfc near S Ontario/Quebec. Shortwave
energy stretching out over the Plains and Mid MS Valley limits
moisture advection into the region, but gradual/weak SW flow will
bring warmer temps with highs back in the 70s and lows in the 50s. A
few diurnal -SHRA and rumbles of thunder can`t be ruled out (mainly
on Labor Day over N-Central and W), but impacts should be low given
limited shear and inconsistent instability in model guidance.
Current PoPs are less than 20% for Labor Day. For the most part,
this provides pleasant weather with light winds and plenty of
sunshine to close out the holiday period.

Attention then turns to a trough upstream over central Canada on
Tue. This trough digs S over Manitoba/Ontario Tue and Tue night,
settling into the Upper Great Lakes on Wed. From here, differences
in positioning and propagation grow into the weekend, however the
general consensus is for a few embedded wrap around shortwaves to
pass over the region as this trough slowly makes its way toward
Quebec for Sun. This sends a sfc trough and cold front across our
region Tue night and Wed, a cold airmass over the Great Lakes for
late next week, and likely another cold front and shortwave pair on
Fri. SHRA and maybe some rumbles of thunder accompany the first cold
front round late in the day Tue into Wed, but instability is low (a
few hundred j/kg of MUCAPE at best). 850mb temps quickly fall near
0C for Wed - Thu, bringing back lake effect -SHRA. A secondary cold
front toward the end of next week brings the last hurrah of PoPs in
the fcst before high pressure briefly returns for the weekend to
gradually bring back drier weather. This colder pattern brings temps
back below normal with highs only in the 50s to low 60s and lows in
the 30s and 40s. An uptick in N becoming W winds is also expected in
the latter part of next week with gusts in the Keweenaw in the 20-30
mph range Wed/Thu.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 112 AM EDT Sat Aug 30 2025

A near repeat of the previous night is expected tonight with VFR
conditions to prevail except for patchy fog at all TAF sites.
So far, IWD has bounced around from VFR to LIFR since 03z and
will likely keep this behavior going through the night. SAW has
finally tanked to LIFR. Confidence is lower regarding fog
potential at CMX, but seeing how they briefly fell just before
sunrise, opting to include a few hours of IFR vis there just
before 12z.

Otherwise, patchy fog burns off with sunrise, giving way to
another fair UP day with light winds, patchy diurnal cu, and
afternoon lake breeze development.

&&

.MARINE...
Issued at 333 AM EDT Sat Aug 30 2025

High pressure residing over the Great Lakes keeps winds below 20 kts
across the lake through the holiday weekend. A cold front and sfc
trough approaching from the NW on Tue increase S to SW winds to 10-
20 kts during the day, with the strongest winds expected over the W
half of the lake. Winds quickly veer NW, increasing to 20-30 kts Tue
night as the cold front presses SE across the lake. A cold airmass
overhead midweek continues N becoming W winds in the 20-30 kt range.
Current probabilities for gales to 35 kts are around 25-50%, highest
over the central third of the lake Tue night through Wed afternoon.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.

&&

$$

SHORT TERM...TAP
LONG TERM...Jablonski
AVIATION...BW
MARINE...Jablonski