387
FXUS63 KDTX 101537
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
1037 AM EST Mon Nov 10 2025

.KEY MESSAGES...

- Cold conditions this morning with wind chills down into the lower
  teens remaining cold this afternoon with highs in the low-mid 30s.

- Warming trend mid to late week.

&&

.UPDATE...

Heart of H3 to H5 trough/low geopotential heights are directly over
Southeast Michigan midday today. Interesting to note on radar mosaic
and Caset-Exeter radar just how sharp the cyclonic flow influence is
over the region with north bound targets/Z returns near Toronto. Due
north to northwesterly winds are here locally and driving
multibanded lake effect snow in the Thumb late this morning. Have had
multiple surface observations of 1/2sm to 1/4sm mile at Bad Axe with
falling snow. Equilibrium heights are forecasted to remain at
approximately 9.0 kft agl with saturation through 21z this afternoon.
Therefore, expecting the lake effect to persist for a number of
hours with localized accumulations continuing. Difficult to get a
handle on impacts as available traffic data has shown little slow
downs to this point. Did go ahead and increased PoPs greater than 60
percent this afternoon. Also increased snow accumulations into the 1
to 3 inch range, but expecting it to remain localized. An absolute
vorticity maximum is forecasted to dig straight southward through
the Straits and into northern IN/OH by this evening. The movement of
this feature should result in some minor retrograding of the lake
effect late this morning and afternoon. Should not be much of a
westward jog, but could be enough to spread snow accumulations to
those areas that have not had much to this point. As flow transitions
more to the northwest in response to the vort max passage, will
likely see an establishment of northwest flow les this evening and
tonight. Will depend on the low/near surface convergence fields but
could see a snow band clip localized portions of the Lake Huron
shoreline from Port Austin down to Harbor Beach tonight. The gridded
forecast has had snow accumulations in tonight period.

&&

.PREV DISCUSSION...
Issued at 527 AM EST Mon Nov 10 2025

AVIATION...

Flow will continue to back from north to northwest this morning and
afternoon which will advect in dry air and keep lake effect activity
east of the terminals. Some residual cloud cover off of Lake Huron
could bring some sporadic mvfr cigs, favored across KPTK to KFNT
this morning, but confidence remains low regarding how well cloud
coverage will hold up given the continued  backing of wind
direction. Otherwise, daytime mixing will mix down gusts around 20
to 23 knots through the afternoon hours.

DTW THRESHOLD PROBABILITIES...

* Low in ceilings aob 5000 feet this morning.

PREV DISCUSSION...
Issued at 400 AM EST Mon Nov 10 2025

DISCUSSION...

The more moderate lake effect snow showers have pulled east of the
eastern Thumb shorelines and thus cancelled the winter weather
advisory for the Thumb. Intervals of lighter lake effect snow
remains possible through the morning. The already cold temperatures
will continue to fall by another degree or two towards sunrise
reaching the low 20s. Combined these temperatures with the elevated
north winds and wind chills will bottom out near 10 degrees. Low to
mid 20s temperatures will also be sufficient to create slick spots
with residual moisture and/or snow on the roadways, especially on
bridges and overpasses. Cautious travel is advised this morning even
as snow has largely ended for most the forecast area.

The northerly winds and warm Lake Huron waters will continue to
churn out lake effect snow across the Thumb through this morning
into the early afternoon. The difference today will be the loss of
greater synoptic moisture as some drier air begins to filter into
the region. Surface dewpoints falling into the low to mid teens.
Soundings at Bad Axe still indicate steep lapse rates through the
DGZ with a saturated boundary layer, but convective depths have
shrunk below 10 kft. This environment should keep snowfall intensity
in check. Winds will also be backing towards the northwest
throughout the afternoon. This will bring about a transition from
Lake Huron moisture to great influence of the Lake Michigan moisture
flux for most of the area. Isolated to scattered light snow
showers/flurries can be expected this afternoon while ongoing lake
effect showers across the Thumb gradually get pushed offshore
towards the evening. The northwest flow will lead to a another
uptick in lake effect snow that may effect the north and eastern
portions of Huron County after 8 pm this evening if wind direction
remains favorable. Locations across the Thumb that can manage to
experience a longer duration of lake effect snow showers may see
accumulation up to 1-2 inches through this evening with greatest
potential across Huron County. Expecting minimal, if any,
accumulations, for remaining areas of southeast Michigan. Core of
the cold thermal trough will be centered over the central Great
Lakes this afternoon, which will only allow daytime highs to top out
in the low to mid 30s.

Tuesday will see a low amplitude ridge early in the day. Then a push
of warm advection along with convergence with low level jet may be
enough to trigger some light snow showers during the afternoon.
Expect some breezy conditions on Tuesday as mixing depths tap into
the stronger low level flow. Warm advection brings temperatures up
into the mid-upper 30s for most of the area with some locations
possibly reaching 40 degrees.

Ridging builds across the central plains and Midwest mid to late
week resulting in mostly quiet weather conditions with the exception
of scattered light precipitation Tuesday night through Wednesday.
Warm advection gains traction in the deeper southwest flow and will
bring temperatures up into the 40s for Wednesday and Thursday and
into the 50s for Friday.

MARINE...

Gusty N to NNE wind gradually backs to NW through the day as broad
low pressure tracks over New England and high pressure builds into
the Midwest. Wind magnitude will be on the order of 20 to 25 kt with
brief occasional gusts to 30 kt possible at times across southern
Lake Huron. This maintains high wave action across the southern
basin and Small Craft Advisories remain in effect through today into
Tuesday. Scattered lake effect snow showers will persist through
this period as well.

Flow shifts to southwest on Tuesday in response to the upstream
ridge axis passing through, causing milder air to work back in. A
strong low-level jet will pass over parts of the central Great Lakes
late in the day into the evening. Increasingly stable thermodynamic
profiles will prevent the higher magnitude of wind aloft from
reaching the surface, but there is moderate confidence on gusts in
excess of 30 kt. Probability for gales remain too low for a Gale
Watch at this time. A cold front moves through on Wednesday,
sustaining a gusty W to NW flow pattern with scattered rain showers
through Thursday. A period of gales will be possible across parts of
Lake Huron Wednesday into Thursday. High pressure then brings
weaker, more variable wind for Friday.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...None.
Lake Huron...Small Craft Advisory until 4 PM EST this afternoon for LHZ422.

     Small Craft Advisory until 10 AM EST Tuesday for LHZ421-441>443.

Lake St Clair...Small Craft Advisory until 4 PM EST this afternoon for LCZ460.

Michigan waters of Lake Erie...None.
&&

$$

UPDATE.......CB
AVIATION.....AM
DISCUSSION...AA
MARINE.......TF


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