184
FXUS63 KDTX 231945
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
345 PM EDT Sun Aug 23 2026

.KEY MESSAGES...

- Breezy and cooler conditions arrive today with scattered showers
into tonight.

- Dry weather Monday into Tuesday with a warming trend. The next
chance of showers and storms is possible late Wednesday and Thursday.

&&

.DISCUSSION...

Stacked low pressure system spinning just to our east over southern
Ontario will lift northeast into Quebec overnight. We`re dealing
with cold advection on the backside of the low today with a strong
mid level wave passing over this afternoon before the low finally
departs. Atmosphere utilizing the low level moisture one last time
this afternoon with a round of scattered showers before ridging
pushes in and dries out the mid levels ending precip chances later
this evening. SPC Mesoanalysis shows around 250 J/kg of CAPE mainly
in the Thumb with a band of low level convergence stretching from
MBS to PHN. This has been enough to generate some showers in the
area. Weak mid level lapse rates and little instability should help
minimize much of any lightning. Cool night in store as dewpoints
have already fallen to around 50 and even the mid 40s across
northern MI. Once the diurnal clouds mix out we should clear out for
the most part. Questionable area will be the eastern Thumb where the
cloud shield from the upper low continues to reach back toward the
area. Clouds would help hold those temps up a few degrees if the
clouds never release.

Surface high builds in tonight for Monday and Tuesday while upper
level heights also inch upwards. We`ll keep the northwesterly flow
Monday helping to hold highs temps on the cool side again in the mid
70s, but the ridge axis passes on Tuesday allowing for some warmer
return flow to get us back up toward 80.

Next trough affect the region mid week with a warm front pushing
north of the area Tuesday evening tied to a low passing through the
northern Great Lakes. Upper level waves start ejecting out of the
trough over the region Wednesday leading to increasing chances of
rainfall before the main trough axis and cold front sweep through
early Thursday.

&&

.MARINE...

Post-frontal breezy northwest flow will persist through tomorrow as
cooler air is ushered into the Great Lakes. Wind gusts ranging
between 20 to 30 knots are expected during this window, along with
some isolated gust potential to 35 knots through this evening,
focused mainly across north-central and central Lake Huron. Given
the lower confidence for any longer duration gale potential, will
continue to preclude any issuance of gale products. Increasing
coverage of rain showers will be likely tonight into tomorrow
morning across Lake Huron, including a very low chance for
waterspouts along any convergence axis. High pressure will then
begin building into the Great Lakes Monday evening, centering over
the region by Tuesday. This will diminish wind speeds tomorrow
night, leading to light winds by Tuesday.

&&

.PREV DISCUSSION...
Issued at 133 PM EDT Sun Aug 23 2026

AVIATION...

Low pressure continues to occlude over the Ontario/Quebec border,
with cyclonic gradient flow on the backside of the low peaking
around 15 knots with gusts up to 25 knots. Wrap-around moisture
pairs with lake moisture flux to support low VFR ceilings through
most of the TAF period as well. Isolated shower coverage peaks
through the diurnal cycle followed by a window of decreasing cloud
coverage to SCT-FEW this evening. A second pool of moisture over
central Ontario releases south tonight into Monday, bringing another
opportunity for low VFR cigs. The airspace will be on the outer edge
of the moisture gradient meaning fluctuations in coverage will be
possible throughout the day. Otherwise, breezy west-northwest winds
and dry conditions expected Monday.

D21/DTW Convection... very low potential for an isolated
thunderstorm this afternoon and evening.

DTW THRESHOLD PROBABILITIES...

* Moderate to high for ceiling 5000 feet or less today and tonight.

* Very low for an isolated thunderstorm this afternoon and evening.


&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement through Monday afternoon for MIZ049.

Lake Huron...Small Craft Advisory until 4 PM EDT Monday for LHZ421-441>443.

     Small Craft Advisory until 4 AM EDT Monday for LHZ422.

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

$$

DISCUSSION...DRK
MARINE.......AM
AVIATION.....MV


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