342
FXUS63 KMQT 130605
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
205 AM EDT Mon Oct 13 2025

.KEY MESSAGES...

- A round of showers presses west to east late tonight through
  Monday. Rainfall accumulations are expected to remain light,
  generally less than 0.25".

- Temperatures will average slightly warmer than normal through
  Monday before becoming more seasonable.

- There is a 40-70% chance for southerly wind gusts greater than
  30 mph this evening into Monday morning, particularly for
  favored downsloping locations of the western and central high
  terrain and Lake Superior shorelines.

- A period of southerly gales around 35 kts is expected over
  central Lake Superior tonight.

&&

.DISCUSSION...
Issued at 347 PM EDT Sun Oct 12 2025

Afternoon RAP analysis and GOES water vapor imagery highlight
upstream development as a vigorous trough over eastern
Montana/western Dakotas supports a 986 mb low over southwest
Manitoba. This is part of a broad mid level trough expanding the
Canadian Prairie and the western CONUS. The ridge axes which once
extended overhead is shifting southeast toward the Lower Great Lakes
and surface ridging extending off a parent high over the St Lawrence
Seaway is weakening.

The trough and seasonably strong surface low over Manitoba lift
northeast through tonight, strengthening the pressure gradient and
southerly flow during this period. As a result, milder and breezier
conditions are expected. Temps this afternoon in the upper 50s to mid
60s settle overnight into the upper 40s to mid 50s. Widespread winds
of 5-15 mph, gusting to 25 mph are forecast. Wind gusts will be
strongest in areas of south-southeast downslope flow where gusts
will frequent into the 20-30 mph range. Probabilistic guidance
aligns well with model soundings, highlighting potential for
stronger winds this evening into early tonight. The EPS and NBM
probabilities highlight between 40-70% chances for gusts between 35 -
40 mph accelerating off the north central and far western high
terrain. The 12Z HREF guidance continues to portray much higher gust
potential, which is often overdone in southerly warm air advection
regimes. Utilizing it as support for higher gust potential and not
an explicit wind gust forecast.

Surface obs indicate a frontal boundary located near the west side
of Minnesota. This is expected to progress toward the CWA, sending a
round of light to occasionally moderate rain showers from west to
east across the UP tonight through Monday. Guidance continues to
favor accumulations between a few hundreths to 0.25", with a 20-40%
chance for higher amounts; best chances reside in the Keweenaw.
Temps on Monday over the far west will struggle to get out of the
50s already being in the wake of the cold front. Elsewhere, temps
look to reach into the low to mid 60s prior to frontal passage.
Breezy west winds continue behind the front in the Keweenaw with
gusts likely between 20-30 mph. Light northwest winds continue
overnight into Tuesday as dry weather returns and temps settle into
the mid 30s to mid 40s.

High pressure moving in for the middle portion of the week leaves
dry, quiet, and more seasonable weather likely through at least
Wednesday night. A ridge riding shortwave Tuesday night may try to
scrape some light showers along the south, but the current forecast
favors antecedent dry air limiting PoPs. PoPs return on Thursday,
continuing through next weekend as this high pressure weakens and
quickly departs to the east. At the same time, the mid level ridge
that had built up over the Midwest breaks down, shifting a troughing
pattern over the region for the weekend.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 205 AM EDT Mon Oct 13 2025

Radar shows a band of rain showers associated with a cold front
entering the far western UP as of 06z Mon, but observations
from around the area show VFR conditions with cigs still mainly
around FL100. Low level wind shear persists at the terminals
thanks to a LLJ bringing south winds of 45-50 kt at FL020. LLWS
will diminish at IWD and CMX by 08-09z and SAW by 10z as the
front progresses eastward across the area through Monday
morning, spreading showers into IWD and CMX through around 12z
and SAW through ~14z. Expect mainly VFR conditions to persist at
all sites, but could see a few brief bouts of MVFR through Mon
morning in passing showers. Winds shift westerly behind the
front by Monday afternoon, diminishing below 10 kt after ~22z
Mon.

&&

.MARINE...
Issued at 347 PM EDT Sun Oct 12 2025

Southeast winds ramp up this afternoon as a strong low pressure
system lifts northeast from Manitoba to Hudson Bay tonight through
Monday. The resulting pressure gradient draped across the Great
Lakes will enable gusty southerly winds upwards of 30-35 kts, mainly
north and east of the Keweenaw where guidance suggests 50-70% chance
for Gales to 35 kts this evening into early Monday morning. Winds
veer west behind a frontal boundary on Monday, gradually settling to
15-25 kts by the end of the day. Winds settle to around 20 kts or
less on Tuesday, save for some stray guts up to 25 kts over the
southeastern waters, as high pressure builds in. Winds settle below
15 kts across the lake Tuesday night, holding through Thursday
morning. High pressure quickly gives way on Thursday, reintroducing
20-30 kt winds to the lake for next weekend.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
  Gale Warning until 8 AM EDT this morning for LSZ244-245-
     264>266.

Lake Michigan...
None.

&&

$$

DISCUSSION...77
AVIATION...CB
MARINE...77