mi discuss
Office: MQT
FXUS63 KMQT 020540
AFDMQT
Area Forecast Discussion
National Weather Service Marquette MI
1240 AM EST Tue Dec 2 2025
.KEY MESSAGES...
- Winter Weather Advisory for moderate to possibly heavy lake
effect snowfall in Keweenaw County tonight into Tuesday
morning. Uncertainty remains high in the exact placement of
the dominant band with a high boom/bust scenario.
- Periods of light to moderate lake effect snowfall is expected
through the week as a cooler than normal airmass resides over
the region.
- The next chance of widespread light snowfall comes with a
fast-hitting Clipper Low Tuesday night into Wednesday.
&&
.DISCUSSION...
Issued at 323 PM EST Mon Dec 1 2025
Afternoon GOES water vapor imagery and RAP analysis show the weak
ridge and surface high pressure over the Lower Great Lakes/Ohio
River Valley drifting east. Temps in the upper teens to mid 20s will
begin their descent as colder air filters in.
A shortwave and weak surface trough press in from the northwest this
evening. Best forcing remains south of the CWA, but flurries and a
few stray light snow showers may graze Lake Michigan shores and
southern Luce County. Accumulations in those areas will be limited
to a few tenths of a inch. The primary concern during this period
into Tuesday will be the LES over Lake Superior. The latest SPC
mesoanalysis indicates -14C to -16C 850mb temps over Lake Superior,
which is currently sitting at an average temp of just above 6C
slightly warmer near the western lakeshores. With delta-Ts of 20-
22C, inversion heights of 5-6 kft, strong low level convergence, and
plenty of moisture available into the DGZ, moderate to heavy LES is
anticipated with the dominant band setting up. The limited view on
the radar mosaic paired with visible satellite show this is well
underway over the west half of the lake. The tricky part of the
forecast will be where this dominant band sets up. With tonights
cold temps in the single digits to teens, a land breeze component
could keep this snowband further off shore and limit snowfall totals
to 1-2". But, if the surface trough is strong enough to shift the
band further south, higher amounts reaching into the 6-12" range
could be realized. Experimental REFS/NBM probabilistic data indicate
40-60% chances for greater than 4" of snow, focused north and west
of US-41. This is also where the same guidance points to moderate to
heavy snowfall rates up to 1"/HR which would reduce visibility.
Given the high boom/bust potential of the forecast and the likely
hazards given the southerly track, opted to hoist a Winter Weather
Advisory for 7 PM EST this evening to 10 AM EST Tuesday. Upgrades to
a warning may be necessary given the boom potential so stay tuned
for forecast updates. Impacts to the morning commute are possible on
Tuesday.
In the wake of this initial wave, southwest flow strengthens again
Tuesday morning in advance of the next system lifting any LES north
away from the UP. Highs will be in the 20s. Dry weather by the
afternoon will be brief, as the next round of widespread snow arrives
Tuesday night.
There remains pretty decent model agreement in an Alberta Clipper
Tuesday night into Wednesday. Even with the subtle differences
between ensemble suites on how far north this low will track,
amounts will not be impressive regardless. Widespread amounts of a
dusting to 1" are the likely solution (60% chance) with higher
amounts to 2-3" over the northwest wind snow belts, primarily
influenced by the lake influence. Strong pressure rises and the cold
airmass of -23C to -25C descending over the region Wednesday into
Wednesday night with the mid level trough will result in a period of
LES and windy conditions. Northwest winds of 20-35 mph are expected
near Lake Superior and in the Keweenaw with widespread 15-25 mph
elsewhere Wednesday into Thursday. Temps on Wednesday will again
lift into the 20s early, but tank to the single digits for most save
for low teens by eastern Lake Superior by Thursday morning. Highs on
Thursday only rise into the teens to low 20s. Expect wind chills
below 0 by Thursday morning across the UP. In terms of trailing LES
over the northwest wind snow belts, NBM probabilities for at least
4"/24HR are ~30% in the Keweenaw/North Central with a 50-75% chance
over the east.
Meanwhile high pressure builds in from the northwest, gradually
working against available moisture Wednesday through Thursday. This
also shifts winds out of the southwest on Thursday, lifting any
lingering LES to the north. This dry period once again does not last
long as the next clipper system arrives Thursday night. That said,
there still is a fair amount of spread on timing/track of this
latter system. What is more certain is LES associated with the
continued colder than normal airmass that accompanies it. An active
pattern including potential additional systems early next week and
periods of LES keep PoPs in the forecast.
&&
.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1240 AM EST Tue Dec 2 2025
MVFR prevails through the rest of the night. There remains a
potential for a lake effect snow band to pivot over the Keweenaw,
with heavy snowfall and IFR-or-worse restrictions possible at CMX.
However, confidence is low, so have continued to handle this
potential with a PROB30 the second half of the night. Otherwise,
expect VFR at all terminals after 12Z Tuesday. Another batch of snow
begins to move into the western UP Tuesday night, with a drop down
to MVFR possible at IWD and CMX towards the end of the forecast
period.
&&
.MARINE...
Issued at 340 PM EST Mon Dec 1 2025
A low pressure trough descends southeast over the lake this evening
shifts winds over the north half of the lake out of the northwest,
settling to around 20 kts or less tonight. Meanwhile, west-southwest
winds across the rest of the lake hold around 15-25 kts. Moderate to
heavy lake effect snow bands across the long axes of the lake will
reduce visibility to less than 1 NM at times overnight into Tuesday.
Significant wave heights settle below 4 ft by Thursday morning.
The pressure gradient tightens with a Clipper Low Tuesday night into
Wednesday. Southwest winds increase once again to 20-30 kts by
Tuesday night, veering northwest Wednesday morning behind the cold
front and maintaining between 20-30 kts into Thursday. This system
brings the best shot at gales to 35 kts during the forecast period
(40-60% Wednesday into Wednesday night, highest chances east) as a
cold airmass descends overhead accompanied by strong pressure rises.
If confidence increases, a Gale Watch would be warranted on the next
forecast package. Significant wave heights build to 6-12 ft, highest
southeast. The elevated winds/waves and cold airmass support light
to moderate freezing spray across the lake, and likely some heavy
freezing spray over the north central waters (~60% chance).
Northwest winds fall back down to 20-30 kt for Thursday, but may
increase again out of the southwest to 35 kts Thursday night into
Friday ahead of the next clipper system. That said, there remains
plenty of uncertainty regarding the exact timing and track of the
late week system.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
Winter Weather Advisory until 10 AM EST this morning for
MIZ001.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
DISCUSSION...77
AVIATION...LC/NL
MARINE...77
Office: DTX
FXUS63 KDTX 020456
AFDDTX
Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
1156 PM EST Mon Dec 1 2025
.KEY MESSAGES...
- Light accumulating snow tonight. South of M-59, 1 to 3 inches of
accumulation expected, with Monroe County seeing the highest total.
North of M-59, just a dusting to maybe a half an inch.
- Temperatures will remain well below normal throughout the week. The
coldest conditions arrive Thursday and Friday with wind chill
values bottoming out at or below zero.
- Arctic front will bring the potential for snow showers late
Wednesday, with some minor accumulation possible.
&&
.AVIATION...
Light snowfall persists over the terminals tonight. Ceilings have
had to contend with formidable low-level dry air, therefore VFR
ceilings have held on longer than expected, for the southern TAF
sites. Visibilities have been more variable, fluctuating between VFR
and IFR, even heading into the peak of the event. Did trend more
optimistic with the 06Z TAF cycle, favoring MVFR conditions (instead
of IFR) into Tuesday morning. Snow concludes from west to east
between 09Z and 12Z. Gradient flow remains light and variable into
the morning hours, becoming westerly.
For DTW...Conditions settle into MVFR for the rest of tonight and
Tuesday morning. Still some opportunities for additional IFR
visibilities with any enhanced snowfall rates. Snow ends around 12Z
with ceilings eventually lifting to VFR, then scattering out.
DTW THRESHOLD PROBABILITIES...
* High for ceiling at or below 5000 ft through midday Tuesday then
low Tuesday evening.
* High for precipitation type as snow tonight and Tuesday morning.
&&
.PREV DISCUSSION...
Issued at 242 PM EST Mon Dec 1 2025
DISCUSSION...
Extremely dry airmass in place over southeast Michigan this morning,
as 12z DTX sounding indicated a PW Value of 0.11 inches, right
around the daily min record.
Thick canopy of high clouds today, coupled with the cold start, has
resulted in temps holding around 30 degrees for the afternoon, a
good 10 degrees below normal.
Still looking a light snow developing this evening/tonight with
decent moisture advection, height falls/upper level PV advection,
and mid level frontal circulation. Top down saturation process may
take much of the evening to saturate the low levels however.
Specific humidity in the 850-700 MB layer still on track to rise to
1.3 g/kg north to 1.75 g/kg along the southern Michigan border.
Despite some of the weak forcing(9-12 hr)/moisture being used up to
saturate the low levels, snowfall accumulations of 1-3 inches are
expected south of M-59. Areas which look to reach 3 inches is Monroe
county and possibly southern Wayne county, as the flow at the sfc to
925 MB is light southeast off of Lake Erie, which should help
accelerate the moistening of the low levels and enhance the qpf a
bit. North of M-59, pronounced surface ridging holding on through
the night, and would expect accumulations a half an inch or less.
Shortwave ridging on Tuesday with the next arctic front still on
track to move through late Wednesday as a strong shortwave/spoke of
energy around the strong polar low near/over Hudson Bay rotates
through the northern Great Lakes Wednesday night. With a little
moisture flux off Lake Michigan and good low level convergence with
the front, do think a line of snow showers will develop. Low level
lapse rates steepen up and some modest cape is generated, which will
flirt with the DGZ. As such, could become a borderline scenario for
snow squalls, as there does look to be 40 knots of flow at 850 MB.
Exact timing of front and magnitude of the cold air sweeping in will
determine. Right now, 850 MB temps progged to drop into the
-15 to -20 C range over the Central Great Lakes Thursday morning,
per 12z Euro. Temps likely hold in the lower 20s during Thursday,
setting us up for mins of zero to 10 above Thursday night. Short
lived warming (but still below normal) ahead of another arctic front
on track to move through for the first half of the weekend, but
uncertainty with the southward push and how fast it washes out.
MARINE...
High pressure will continue to push off towards the east and away
from the Great Lakes this afternoon, while maintaining light winds
across the southern half of the region. Over the northern Great
Lakes, persistent southwest flow will continue through tonight as
the broad low pressure system continues to reside over the Hudson
Bay region. A system trailing the high crosses the Ohio Valley late
this afternoon into Tuesday offering light snow chances but
otherwise brings minimal local marine impacts. Next significant
system arrives Wednesday as a strong arctic cold front drops out of
northern Ontario resulting in both strong preceding southwest winds
and trailing northwesterly winds as the coldest air of the season
thus far moves over the Great Lakes. Currently, greatest chances
(~40-50%) at seeing gusts to gales occur during the preceding
southwest aided by longer fetch over the central portions Huron.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...None.
Lake Huron...None.
Lake St Clair...None.
Michigan waters of Lake Erie...None.
&&
$$
AVIATION.....KGK
DISCUSSION...SF
MARINE.......KDK/SS
You can obtain your latest National Weather Service forecasts online
at www.weather.gov/detroit.
Office: APX
FXUS63 KAPX 020500
AFDAPX
Area Forecast Discussion
National Weather Service Gaylord MI
1200 AM EST Tue Dec 2 2025
.KEY MESSAGES...
- Several inches of lake-enhanced snow expected tonight along the
Lake Michigan collar counties of northwest lower Michigan...as well
as for southeast sections of eastern upper Michigan.
- Next wave delivering more lake enhanced snow and cold temperatures
arrives Wednesday through Thursday night.
- Weather remains relatively active thereafter, with more chances
for snow showers at various times right through the weekend.
&&
.SHORT TERM /THROUGH TUESDAY/...
Issued at 230 PM EST Mon Dec 1 2025
Pattern Synopsis/Forecast:
Fast paced northern stream flow regime continues to dominate Great
Lakes weather early this afternoon...with overhead mid level ridging
already showing signs of succumbing to next quickly approaching
shortwave trough currently cutting across the upper Mississippi
Valley. Subsidence and drying with that passing ridging has largely
ended the more organized lake snow threat (for now), with just some
lingering very light snow showers/flurries rotating off northern
sections of Lake Michigan. Otherwise, a dry and fairly uneventful
day, with current temperatures mostly in the 20s.
Upstream wave and attendant weak surface trough expected to work
steadily east, crossing our area later tonight. This wave will help
drum up a rather healthy lake enhanced snow response for a few
select areas tonight.
Primary Forecast Concerns:
Main focus centers on lake enhanced snow evolution, amounts, and
attendant headline considerations tonight.
Details:
Kinda a classic southwest flow lake enhanced snow response expected
to unfold this evening as fast moving shortwave trough/attendant
surface trough helps reinvigorate ongoing convection across northern
Lake Michigan. Surge of deeper synoptic moisture/seeder feeder
processes, enhanced corridor of low level convergence, and
respectable convective cloud depth to H7 should help organize a band
of snow along the Lake Michigan collar counties of northwest lower
Michigan (including parts of Cheboygan County)...with that band
likely extending along the M-134 corridor of southern Mackinac and
Chippewa Counties in eastern Upper Michigan. Strong signal that max
and intense omega will be pegged solidly within the dendritic growth
region... easily supporting snowfall rates approaching/exceeding
(perhaps significantly so) an inch per hour at times within this
band by later this evening into the early overnight. Emmett and
Cheboygan Counties appear especially under the gun...with continued
signal of enhanced low level convergence... especially so along and
north of M-68 and along and west of I-75. Wouldn't be surprised to
see snow totals approach and even exceed double digits in a
relatively narrow corridor of Emmet and Cheboygan Counties...with
several inches elsewhere in the Winter Weather Advisory areas. Focus
for best snows again will be a relatively narrow one, with large
sections of the headline areas likely falling well short of actual
headline criteria snow amounts. Band should get punted a bit inland
early Tuesday morning...losing both intensity and organization as it
does so as low level convergence and connection to Lake Michigan
moisture contribution are both lost. Otherwise, shortwave itself
will produce some much lighter snow showers elsewhere, with
accumulations mostly under an inch.
Rapid drying and development of warm air advection should largely
end any organized snow shower threat heading through Tuesday.
Lows tonight mostly in the teens to lower 20s, with highs Tuesday in
the upper 20s to lower 30s.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
Issued at 230 PM EST Mon Dec 1 2025
Pattern Synopsis/Forecast:
Fast paced pattern set to continue through the duration as northern
stream flow regime continues to dominate the Great Lakes. Various
waves set to cross the area, each bringing renewed lake snow
concerns and reinforcing shots of colder air into the region.
Primary Forecast Concerns:
Temperature trends and addressing additional snow concerns through
the period.
Details:
No rest for the wary, with next shortwave trough expected to race
across the area Wednesday and Wednesday night. Again, conditions
look rather respectable for a decent pre-frontal southwest flow lake-
enhanced snow response into the shoreline areas of northwest lower
Michigan...as well as sections of eastern upper Michigan. Duration
will be a short one for best synoptic contribution, but could easily
see several inches of accumulation in these areas. Lighter snows
expected elsewhere with the wave passage. Post wave response is one
of rapid drying and subsidence in gusty northwest wind regime...
especially across northern Lake Michigan. Moisture remains a bit
more robust across Lake Superior, supporting a bit more organized
and intense lake effect snow into the eastern upper snowbelts
Wednesday night into Thursday morning. Still expecting snow showers
to rotate into northwest lower Michigan, but as of now it appears
any accumulations with the lake effect portion of this event will
remain minimal. Perhaps biggest story will be the shot of some
modified Arctic air that will sweep across the region with this
wave. Current trends support highs Thursday perhaps not breaking 20
degrees across interior areas...with lows Thursday night in the
single digits and teens. Of course, somewhat gusty winds will make
it feel several degrees colder yet, with wind chill readings likely
in the single digits.
After a brief break Thursday night into early Friday, next in the
series of shortwave troughs looks to arrive later Friday into Friday
night. And, much like its predecessors, should again drum up a
decent southwest flow lake enhanced snow response late Friday into
Friday evening, with more pure northwest flow lake effect behind it
into Saturday. Temperatures will remain several degrees below
normal, continuing at least some lake snow threat right into Monday.
&&
.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1156 PM EST Mon Dec 1 2025
Heavy lake effect snow continues at PLN about half-way thru the
overnight, before exiting east. MBL/TVC will have periods of
IFR for the overnight as well. Then improving conditions, with a
mix of VFR and MVFR for the day on Tuesday. Light winds.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...Winter Storm Warning until 7 AM EST Tuesday for MIZ016.
Winter Weather Advisory until 7 AM EST Tuesday for MIZ017-020-
021-025-031-088-096-097-099.
MARINE...None.
&&
$$
SHORT TERM...MSB
LONG TERM...MSB
AVIATION...JZ
Office: GRR
FXUS63 KGRR 020508
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
1208 AM EST Tue Dec 2 2025
.KEY MESSAGES...
- Localized heavy lake enhanced snow continues
- Light snow tonight /mainly south/
- Below normal temps with additional snow chances rest of week
&&
.DISCUSSION...
Issued at 310 PM EST Mon Dec 1 2025
- Localized heavy lake enhanced snow continues
Localized heavy lake enhanced snow continues this afternoon from
Grand Haven north to near Muskegon. This snow event has been
reasonably well handled /at least thus far/ by high resolution
models. It is being driven by a persist low level convergent zone,
coupled with respectable over-water instability /featuring water
temps near +9C and 850 mb temps around -10C/. WSW-ENE oriented
snow band is drifting northeast as boundary layer winds become
S-SW. Snow will likely increase further in the coming hours as
mid-upper moisture streams in overhead. Though most of the
synoptic snow from this energy aloft will remain south of MKG and
vicinity, the lake enhanced snow should increase due to seeder-
feeder processes.
High resolution guidance - including HREF/HRRR/NAM - suggest
convergent zone will drift slowly northward tonight...likely exiting
Ottawa county by early evening and then impacting Oceana/Muskegon
and eventually Mason counties /though confidence is dwindling that
Mason county will receive big impacts/. Made a late decision to put
Ottawa county back into the Winter Storm Warning, given ongoing
heavy snow in Grand Haven and how slow the snow has been to drift
north. With focused lift within the dendritic growth zone,
guidance supports 70-80% chance of exceeding 8 inches near the
coast /particularly Muskegon and Oceana counties/. Typical of lake
induced snow, spatial variability will be great and if band
becomes stationary, local accumulations could *greatly* exceed 8
inches.
- Light snow tonight /mainly south/
Mid level impulse over the Central Plains late this afternoon
will race across the Ohio Valley to mid Atlantic states by early
Tuesday. Associated snowfall will spread into the Ohio Valley and
lower Great Lakes late this afternoon and tonight, and impact much
of the GRR forecast area. Limited forcing should preclude much
more than 1-2 inches... mainly south /and away from Lake Michigan/.
This light snow will end by daybreak Tuesday.
- Below normal temps with additional snow chances rest of week
As winds turn NW on Tuesday behind tonight's system, lingering snow
showers along the lake shore should quickly diminish and push
inland. Little additional accumulation expected.
The remainder of the work week and into next weekend will feature
clipper like systems moving rapidly eastsoutheast out of Canada
and across the Great Lakes region. These features may provide
additional bouts of snow and/or lake enhanced snow, as well as
reinforcing pushes of colder air. The first system will pass about
Wednesday, and bring /sharply colder air/ for Thursday, when
highs will only be around 20F -- easily some of the coldest air
of the season thus far. Another system will impact the region
about Saturday. High temperatures Wednesday through next weekend will
generally be in the 20s to lower 30s, some 10-15F below normal
for the first week of December.
&&
.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1207 AM EST Tue Dec 2 2025
IFR conditions will be widespread in light snow overnight.
Heavier snow with a lake effect band is expected to affect MKG
after 08Z and could bring brief LIFR conditions. Conditions will
improve Tuesday morning as the snow moves out and VFR conditions
should prevail after 18Z.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Winter Storm Warning until 7 AM EST this morning for MIZ037-043-
050-056.
Winter Weather Advisory until 7 AM EST this morning for MIZ038-
044.
MARINE...None.
&&
$$
DISCUSSION...Smith
AVIATION...Ostuno
