NWS Forecast Discussion

435
FXUS63 KDTX 250752
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
352 AM EDT Sun Oct 25 2026

.KEY MESSAGES...

- A Dense Fog Advisory is in effect for SE Michigan until 10 AM this
  morning, except for the Tri Cities and northern Thumb.

- There is potential for more dense fog Monday morning with similar
  late morning dissipation timing.

- High temperatures increase to around 70 today before a dry cold
  front drops readings back into the upper 50s to low 60s Monday and
  Tuesday.

- Dry weather continues through the middle of next week.

&&

.DISCUSSION...

High pressure centered on the mid Atlantic coast extends back across
the Ohio valley while remaining the primary weather influence in SE
Mi today. As has been the case the last few mornings, fog is once
again a factor leading up to sunrise with a slightly different
footprint each night depending on boundary layer wind direction. The
SE component this morning has a plume augmented by Lake Erie and St
Clair moisture moving inland leading up to forecast issuance time.
Hi-res model wind guidance indicates continued veering of the
boundary layer flow that favors a shift toward the north and east
during the early morning. The Dense Fog Advisory factors this in
although with a chance for additional refinement on areal coverage
based on observations leading up to sunrise.

Conditions otherwise exhibit thickening mid and high clouds moving
in ahead of the Midwest frontal system. The leading low to mid level
moisture axis is also producing pockets of radar returns from NW
Lower Mi back into southern WI. Model depictions of theta-e
advection are modest over top of dry air below 700 mb leaving little
more than virga indications through the day. High temperatures near
70 are the weather highlight, averaging 10 to 15 degrees above
normal for late October.

The surface cold front is slightly more productive as it enters
northern Lower Mi this evening with the chance for a sprinkle
grazing Saginaw Bay and northern Thumb by sunrise Monday. Even that
tends to fade as the low level frontal zone settles farther south
from mid level short wave and upper level jet support that is well
north in Canada. The system lacks moisture but does carry in enough
cooler air to drop temperatures back down toward more typical late
October readings in the upper 50s and lower 60s Monday afternoon and
lows in the mid 30s to around 40 by Tuesday morning.

The mid to late week period is set for resumption of above normal
temperatures as low pressure organizes across the Plains and central
Canada. The early week Great Lakes front stalls in the Ohio valley
and is then pulled back north across the area by the Plains to
Midwest low pressure system. Solutions among the 25/00Z models are
once again lean on QPF due to limited forcing this far east along
the warm front. Prospects for rain look better along the trailing
cold front expected in Lower Mi late Thursday into Friday.

&&

.MARINE...

An uptick in southwest winds over Lake Huron is anticipated today,
ahead of a cold front that will slowly drop south across the region
later today through tonight. Overall, the front is progged to weaken
and slow down as it moves through. Thus, shower chances are highest
up across northern portions of Lake Huron today. By morning Monday,
post-frontal northerly winds will prevail across Lake Huron. As the
front continues to sag southward these north winds will gradually
take over across Lake St. Clair and the Michigan waters of Lake Erie
during the day Monday. With the return of onshore flow, waves build
to around 2-3 feet along the Lake Huron shoreline. Falling short of
small craft concerns, but something to keep an eye on.

High pressure quickly transits the region Monday night into Tuesday,
moving across eastern Canada and into New England area. This
trajectory puts us in a favorable environmental for more onshore
flow as north winds become northeast and easterly Monday night
through Tuesday. The pattern then becomes more progressive, with a
series of low pressure systems tracking through the western Great
Lakes region.

&&

.PREV DISCUSSION...
Issued at 1150 PM EDT Sat Oct 24 2026

AVIATION...

Generally dry and stable conditions will persist throughout
southeast Michigan this period, as high pressure centered to the
east maintains control. This environment will again offer a
favorable environment for some degree of fog formation overnight
into Sunday morning. Prevailing light low level east to southeast
flow will support moisture flux off lake Erie, with a noted increase
in fog just south of the Detroit corridor already. This suggests an
increasingly likelihood for LIFR fog to emerge across this area
during the early morning. Less confidence overall toward the north,
but with some persistence within this pattern suggesting the
likelihood remains high enough to maintain LIFR in the forecast for
all locations. Standard improvement in conditions where fog becomes
dense during the late morning hours, leaving another day of
VFR/clear skies into the afternoon and evening Sunday.

D21/DTW Convection... Thunderstorms are not forecast through the TAF
period.

DTW THRESHOLD PROBABILITIES...

* Moderate for cigs/vsby below 200 ft and/or 1/2SM Sunday morning.


&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...Dense Fog Advisory until 10 AM EDT this morning for MIZ055-060>063-
     068>070-075-076-082-083.

Lake Huron...None.

Lake St Clair...None.

Michigan waters of Lake Erie...None.

&&

$$

DISCUSSION...BT
MARINE.......JA
AVIATION.....MR


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at www.weather.gov/detroit.

NWS DTX Office Area Forecast Discussion