Shingleton, Michigan Weather Forecast Discussion

678
FXUS63 KMQT 230031
AFDMQT
Area Forecast Discussion
National Weather Service Marquette MI
831 PM EDT Mon Sep 22 2025
.KEY MESSAGES...
- Scattered showers and storms through this evening. A strong storm
or two can`t be ruled out, but severe weather is not expected.
- Patchy dense fog expected again tonight, reducing visibility down
to 1/4 mile at times.
- Seasonable temperatures continue through the end of the week.
&&
.DISCUSSION...
Issued at 320 PM EDT Mon Sep 22 2025
Afternoon water vapor satellite imagery shows a shortwave trough
centered over the far western UP and Lake Superior, spurring
widespread shower activity over the region. A line of showers and
thunderstorms currently arcs SE from the Keweenaw over Lake Superior
and into the central UP. A mid level dry slot is working into the
western UP and bringing some partial clearing to those areas, which
could aid in destabilization for the remainder of the day. Latest
guidance and mesoanalysis indeed indicate a bit more instability to
work with than yesterday, with MUCAPE values on the order of 1000-
1400 J/kg through later this afternoon. As such, can`t rule out a
few stronger thunderstorms. Shear remains rather modest in the 20-25
kt range and should therefore continue to limit severe potential,
but it wouldn`t be out of the question to see some small hail in
stronger storms through this evening. Heavier showers and storms
will remain capable of producing locally heavy rainfall given tall,
skinny CAPE profiles and PWAT values of 1-1.25 inches , with a few
spots along the Keweenaw already reporting over an inch of rain
today. That said, still expect most locations to end up with lighter
amounts of a quarter inch or less given the hit of miss nature of
the precipitation.
Showers will begin to taper off from west to east overnight as the
shortwave tracks east along the south shore of Lake Superior.
COnditions will once again be conducive to fog formation tonight
into Tuesday morning given abundant low level moisture and light
winds. Will have to monitor the eventual need for another round of
dense fog headlines overnight based on observational trends. Tuesday
will be mostly cloudy across the area, with shower activity largely
confined to the eastern half. Could see a few thunderstorms linger
across the far eastern extent of the area towards Luce County in
closer proximity to elevated instability and upper level forcing.
Expect similar temperatures to today with highs mostly in the 60s to
around 70 along the WI border.
There is still some question as to exactly how the low departing our
area tonight will interact with the next trough moving out of the
Rockies during the middle of the week. The bulk of the guidance
depicts the low retrograding southwest from Ontario and lingering
over Lower Michigan through Thursday. Meanwhile, the axis of a
positively tilted upper level ridge will nose into Lake Superior and
the UP from the northern Plains. Models therefore continue to keep
the area dry from Wednesday onward, with precipitation associated
with the low remaining to our south. Will nevertheless have to
continue to keep an eye on the potential for a few stray showers to
clip parts of our area during the latter half of the week.
Otherwise, temperatures remain near or slightly above seasonal norms
through the period, with highs in the upper 60s to low 70s, coolest
near Lake Superior. Morning lows will also trend a bit cooler,
dipping back into the 40s as clearer skies allow for better
radiative cooling. Finally, models continue to depict a vigorous
upper trough moving across northern Ontario this weekend and
dragging a cold front across the Upper Great Lakes. Models have
trended a little drier in keeping any precipitation associated with
this feature north of the UP, but forecast confidence remains low at
this time.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 830 PM EDT Mon Sep 22 2025
TAF sites remain in the cyclonic flow of upper level low, but dry
slot as helped to push lingering rain showers and thunderstorms to
the east. Nonetheless, lingering moisture in combination with
upslope flow will cause low clouds and fog to filter back into all
TAF sites overnight. So, expect another night of widespread
LIFR/VLIFR conditions at all TAF sites. After sunrise Tuesday
morning, visibilities will slowly improve to MVFR/VFR levels. But,
cigs will be slow to improve with MVFR/IFR persisting into tomorrow
afternoon.
&&
.MARINE...
Issued at 320 PM EDT Mon Sep 22 2025
Generally light NE breezes persist over the lake through mid week,
perhaps gusting as high as 15 kt at times Tuesday into Wednesday.
Winds are expected to remain below 20 kt through at least the next
few days, with significant wave heights of 2 ft or less through the
period. A pair of fronts sweeping across the lake late in the week
will shifts winds around to the west and potentially bring some 20-
25 kt gusts late THursday into Friday and again on Saturday. Medium
range currently depicts around a 30-40% chance for winds to reach
small craft advisory criteria in that time frame, but forecast
confidence remains relatively low at this time. Otherwise, scattered
showers and thunderstorms will continue over the lake into this
evening and then dissipate overnight as a disturbance moves east
across the region. Patchy dense fog will be a concern again tonight
into Tuesday morning.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
  Dense Fog Advisory until 5 AM EDT Tuesday for LMZ221-248-250.
&&
$$
DISCUSSION...CB
AVIATION...TDUD
MARINE...CB

NWS MQT Office Area Forecast Discussion