636
FXUS63 KDTX 041638
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
1138 AM EST Wed Nov 4 2026

.KEY MESSAGES...

- Mild still today with light rain showers around for much of the
day.

- Briefly drier to start Thursday before scattered shower return
late Thursday-Friday.

- Temperatures return to normal values to end the week.

&&

.AVIATION...

A plume of deep layer moisture will continue to lift across Se Mi
this afternoon in advance of a cold front. Area observations
indicate widespread MVFR ceilings likely to prevail into the early
evening. There have been observations showing IFR ceilings along a
secondary low level moisture influx just to the southwest of the
terminals, which may lead to some intervals of IFR ceilings this
afternoon. There will likely be fluctuations in the frequency of
wind gusts over 20kt this afternoon. The southerly gradient flow
will sustain 30 knot winds down to 2k feet. A shallow near surface
stable layer will suppress gusts at the surface periodically. The
cold front will progress across Se Mi between 02Z and 03Z this
evening, causing a wind shift to the southwest. Post frontal cold
air advection will support increasing chances for ceiling heights to
rise to VFR within the post frontal environment.

For DTW...Current trends and available guidance suggest ceilings
below 2000 feet through the afternoon into the evening. A wind shift
from SSW to SW associated with the cold front is forecast between
02Z and 03Z this evening. While ceilings are forecast to rise post
frontal passage, current model guidance suggest they will remain aob
5000 feet into the overnight.

.DTW THRESHOLD PROBABILITIES...

* High for ceiling 5000 ft or less today. Medium tonight and
  Thursday morning.

&&

.PREV DISCUSSION...
Issued at 319 AM EST Wed Nov 4 2026

DISCUSSION...

Occluding low pressure continues to lift into the northern Great
Lakes shifting LLJ structure over the Mississippi up into the
southern Great Lakes. Connection to the Gulf draws anomalous
moisture into SE MI this morning as PW values push 1.5", near daily
climatological maxima, supporting widespread showers throughout the
morning into this afternoon. Gusty southerly winds also accompany
this structure as diurnal mixing at least partially taps into 30-
35kt flow at 925mb resulting in wind gusts generally in the 25-30mph
though with peak potential towards 35mph. LLJ forcing shifts east
into Ontario by the latter half of the afternoon tapering off wider
spread rain and transitioning to pockets of lingering drizzle/light
rain. Secondary window for greater coverage arrives this evening as
a broken line of showers tied to the cold front cross the state.

Significantly drier airmass trails this cold fropa late tonight as
the system`s dry slot works across SE MI through the first half of
Thursday. Southwesterly winds post-frontal winds moderate the
magnitude of cold advection keeping slightly above normal
temperatures around with highs in the upper 50s to around 60. The,
by this point, closed low then sinks southeast across Lake Huron
latter half of Thursday into Friday offering another period of
scattered light showers. Secondary cold front eventually sweeps
through the region Friday morning bringing both a window of enhanced
shower coverage as well as briefly ushering in a seasonably average
airmass to close out the week. Near to sub 0C 850mb temps result in
highs only around 50, give or take a couple degrees either side,
both Friday and Saturday. Long range models favoring low amplitude
ridging redeveloping over the central CONUS by early next week which
would bring back above normal temps to SE MI.

MARINE...

Low pressure occludes over the western Great Lakes today,
maintaining moderate south to southeast wind across the area today.
Warm air aloft maintains stability over the lakes that will limit
the higher magnitude wind from mixing down. However, gusts as high
as 25 to 30 kt are expected over the open waters of Lake Huron this
afternoon and evening while shorter fetch over the nearshore waters
will limit gusts to the 20 to 25 kt range there. A Small Craft
Advisory is in effect for the Thumb shoreline where wave heights are
forecast to build over 4 feet. Saginaw Bay, Lake St. Clair, and
western Lake Erie may see a brief period of gusts in excess of 25 kt
late afternoon, but confidence is too low for an advisory at this
time. A cold front brings light rain late in the day and into
tonight with wind veering to southwest behind the front after
sunset. The weakening low pressure meanders across the western Great
Lakes on Thursday while deeper mixing brings southwest wind to 25 kt
across Saginaw Bay. A stronger cold front then tracks southward
across the region on Friday. This brings gusty north and northeast
wind that shifts northwest and weakens by Saturday. Additional light
rain will accompany this frontal passage.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...None.
Lake Huron...Small Craft Advisory until midnight EST tonight for LHZ441>443.

Lake St Clair...Small Craft Advisory until midnight EST tonight for LCZ460.

Michigan waters of Lake Erie...Small Craft Advisory until midnight EST tonight for LEZ444.

&&

$$

AVIATION.....SC
DISCUSSION...KDK
MARINE.......TF


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