677
FXUS63 KDTX 192016
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
316 PM EST Wed Nov 19 2025

.KEY MESSAGES...

- Dry conditions with highs mainly in the 40s Thursday.

- A low chance for rain or drizzle Thursday night along and behind a
cold front.

- High pressure will move into the region for the beginning of the
weekend with highs in the low 50s.

&&

.DISCUSSION...

Surface high pressure is centered directly over the Great Lakes this
afternoon. Both 19.12z KDTX raob and forecast soundings highlight a
very dry air mass in place with PWATs of around 0.25 inch and very
strong static stability between 2.0 and 8.0 kft agl. Model data
supports the center of high pressure passing eastward this evening
eventually allowing some semblance of weak southerly return flow.
The weak southerlies are non trivial as a blanket of stratus remains
in place across portions of Southwest Lower Michigan including
Lenawee County. In addition, dampened shortwave energy embedded
within the broad mid to upper level ridge is expected to increase
high cloud over the state. The net result will be increasing clouds
tonight that could impact low temperatures particularly over
southern sections of the forecast area.

Main weather driver for the late Thursday and Friday period is a
deep potential vorticity anomaly that will tumble and dig into the
northern Great Lakes. Forecast data remains steadfast that
anticyclonically curved upper level jet axis with residual high
stability above 4.0 kft agl will maintain quiet weather close to and
arguably even with the the arrival of cold front. Latest timing has
the surface cold front through the Tri Cities at 12z Friday and
around 18Z at Detroit down to the Ohio border. Signal out of the
models shows some saturation potential/drizzle signal in advance of
and immediately behind the front where some light measurement could
be observed. The inherited 15-20 percent PoPs are fine. 850mb
temperatures are not forecasted to drop much at all given the warm
midlevels, so highs Friday will likely be dependent on insolation,
readings in the 50s.

Big differences exist amongst the global deterministics with the
northern edge of the precipitation shield Friday as shortwave energy
pushes eastward through the Tennessee River Valley. Given the strong
southern branch that is far to the south of Lower Michigan and
continued strong midlevel stability here locally, do not have much
confidence in the PoPs the available guidance are providing. With
that said, will leave the PoPs alone at below 40%.

Strong model consensus continues that Southeast Michigan will reside
in a quiet and dry location relative to the upper level jet axis.
Ridging is anticipated through the end of the weekend. Highs in the
upper 40s to lower 50s.

&&

.MARINE...

Influence of high pressure wanes through the night as it shifts
toward the northeastern US. Southwesterly winds begin strengthening
by Thursday afternoon in response to low pressure tracking over
northern Ontario with peak gusts reaching 20-25kts by late evening.
The associated cold front crosses the central Great Lakes overnight
bringing some scattered rain shower chances as well as ushering in
renewed colder NW flow. With the region residing on the fringe of
this system, only modest cold advection follows which is expected to
keep gusts sub 30kts across the northern and central portions of
Lake Huron with the southern half of the region peaking closer to
20kts. High pressure then briefly works in by Friday night bringing
light winds to start the weekend.

&&

.PREV DISCUSSION...
Issued at 1234 PM EST Wed Nov 19 2025

AVIATION...

High pressure centered right over the Great Lakes has maintained
mostly clear skies, with high-based cirrus now streaming in from the
west. Wind direction will veer southeasterly and eventually
southerly as high pressure departs the region. This will allow the
stagnant pool of low-level moisture to slowly expand back into
Michigan from south to north through the overnight hours. The MVFR
cigs seen along and south of the Michigan border will fill in across
all terminals as a result, and will hold for through the remainder
of the TAF period.

DTW THRESHOLD PROBABILITIES...

* High in cigs aob 5kft by tomorrow morning.


&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...None.
Lake Huron...None.
Lake St Clair...None.
Michigan waters of Lake Erie...None.
&&

$$

DISCUSSION...CB
MARINE.......KDK
AVIATION.....AM


You can obtain your latest National Weather Service forecasts online
at www.weather.gov/detroit.