887
FXUS63 KMQT 071758
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
158 PM EDT Tue Oct 7 2025

.KEY MESSAGES...

- A widespread freeze/frost is possible for inland areas
  tonight. A freeze warning and frost advisory have been
  issued.

- Frost and/or freeze conditions will be possible again
  Wednesday night.

&&

.DISCUSSION...
Issued at 314 AM EDT Tue Oct 7 2025

A weak surface trough is noted over western Lake Superior underneath
the leading edge of a broad trough that extends across much of
central Canada. A 300mb jet streak ahead of the two supported
widespread lift last evening, which resulted in scattered light
radar returns overhead. The dry, near surface airmass though
prevented much, if any rain, from reaching the ground. Temperatures
so far have fallen into the 40s for most, with a couple of high 30s
being observed as well. With clear skies noted on GOES IR imagery,
additional cooling is expected, with potential for widespread mid to
upper 30s by sunrise across the interior west/central.

A weak cold front upstream in the Northern Plains will move eastward
through Lake Superior today and the resultant increasing pressure
gradient and post frontal cold air advection will enable gusty winds
to develop across the region. Strongest winds near 35 mph will be
this morning in the Keweenaw from the west, which will shift
northwesterly by afternoon. Elsewhere, 20 mph gusts should be
expected, with upwards of 30 near the Lake Superior lakeshore east
of Marquette. Temperatures look to peak in the mid to upper 50s for
most, save low 60s south-central. The airmass will continue to dry
through the day as high pressure presses eastward into the area and
subsidence increases. With PWATS falling to near 0.2 inches by
tonight, light winds developing, and 850mb temps falling to -3 to -
1C, freeze conditions look good tonight for interior areas of
central and western Upper Michigan. NBM probabilities suggest 60-85%
chance for these areas to fall to at least 32 degrees and 20 to 35%
chance of falling below 28F. With this in mind and the classic
signals for effective radiational cooling, opted to upgrade the
inherited freeze watch to a freeze warning for areas removed
from the lakeshores of central and western Upper Michigan. For
the Keweenaw and east, went with a frost advisory given the
slightly warmer anticipated temperatures.

Dry conditions prevail Wednesday and Thursday as mid-level ridging
extends northward from middle CONUS into Canada and surface high
transits Upper Michigan. A slight warming trend is noted between the
days, with Wednesday in the mid to upper 50s climbing into the 60s
for many areas Thursday. Frost/freeze conditions look possible again
Wednesday night, with the risk area now stretching into eastern
Upper Michigan. Ridge axis shifts through the Upper Great Lakes
Thursday afternoon with a sharp closed low/shortwave dropping
southeast from Manitoba into Ontario early Friday. An
associated cold front will be pulled through the region Friday,
with chances for precip ahead of the boundary late Thursday
night into Friday morning. Another surface high and mid-level
ridge move in afterwards, which favors dry conditions until
Sunday.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 156 PM EDT Tue Oct 7 2025

VFR conditions prevail during the 18Z TAF period. Northwest winds
remain elevated this afternoon between 10-15 kts in the wake of the
cold front now progressing over the eastern UP. Gusts are expected
up to 30 kts at CMX and around 20 kts at SAW until sunset when winds
shift more northerly and diminish. At that point, a colder airmass
passes overhead and lake effect cloud cover returns. Best coverage
will be at SAW where a few sprinkles could be seen and periods of
high-end MVFR cigs can`t be ruled out (15-25% chance). CMX may see
broken skies at times, but confidence was too low to include,
especially given VFR cigs should persist. Mostly clear skies are
expected at IWD. Skies scatter out Wednesday morning as high
pressure centers overhead.

&&

.MARINE...
Issued at 314 AM EDT Tue Oct 7 2025

West winds will strengthen to 25 kts ahead of an approaching cold
front early this morning. The cold front will push through the area
by mid-late morning with winds becoming northwest to 30 knots behind
the front. A few gusts to gale are possible at the higher platforms.
Winds become light on Tuesday night, below 20 kts as high pressure
settles into the region. Low pressure tracking through Ontario will
bring increasing southerly winds for Thursday into Friday, possibly
up to 30 kts.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Frost Advisory from midnight tonight to 10 AM EDT Wednesday
     for MIZ001-003-006-007-014-085.

  Freeze Warning from midnight EDT /11 PM CDT/ tonight to 10 AM
     EDT /9 AM CDT/ Wednesday for MIZ002-004-005-009>013-084.

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

&&

$$

DISCUSSION...JTP
AVIATION...77
MARINE...JTP