Area Forecast Discussion
Issued by NWS Detroit/Pontiac, MI
Issued by NWS Detroit/Pontiac, MI
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FXUS63 KDTX 021054
AFDDTX
Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
654 AM EDT Fri Oct 2 2026
.KEY MESSAGES...
- Showers end early this morning, with developing sunshine today.
Cool tonight with mins mainly in the upper 30s to lower 40s.
- A pleasant weekend with highs in the low to mid 60s on Saturday
and around 70 degrees on Sunday. A low chance of showers late
Saturday night into Sunday morning (primarily near Saginaw Bay).
- Dry weather continues early next week, with chilly lows in the 30s
to near 40 possible Tuesday morning.
&&
.AVIATION...
Midlevel dry air advection will occur by 15z with low level flow
trajectories becoming strongly anticyclonic by 18z. Remnant moisture
will bring the potential for MVFR ceilings the first hour or two of
the period. VFR conditions this afternoon with SKC tonight.
D21/DTW Convection...No thunderstorms forecasted.
.DTW THRESHOLD PROBABILITIES...
* None
&&
.PREV DISCUSSION...
Issued at 308 AM EDT Fri Oct 2 2026
DISCUSSION...
A fast, progressive flow will persist over the northern CONUS over
the next week, although a deeper trough does look to develop over
New England on Monday.
Rain looks to be coming to end by around 8 AM, with the 850 MB theta-
e ridge already well southeast of the state. A shortwave trough is
working through the northern Great Lakes this morning, with an
impressive mid level dry slot arriving, as 700 MB dew pt depressions
reach 30 to 50 C by day`s end.
Expansive high pressure builds in tonight, with the center of the
high (1028 MB) parked over northern Lower Michigan by 12z Saturday.
NBM temps on are on the colder side. With this morning`s rainfall
soaking the ground and a lack of strong dry advection near the
surface, surface dew pts are expected to remain solidly above
freezing; thus, no frost is expected. In fact, there is more concern
with northerly flow off Lake Huron leading to low clouds over the
eastern Thumb region, keeping overnight mins elevated above 40
degrees.
Slow return flow around the departing high on Saturday, but backed
southeast surface flow should keep temps in the low to mid 60s,
slightly below normal.
The next Pacific shortwave currently along the southern British
Columbia coast on track to move into the central Great Lake Saturday
night, with the cold front moving through on Sunday. The greatest
height falls and forcing will be directed toward Saginaw Bay. Euro
ensembles suggests significantly higher pops for the northern half
of the CWA than the dry outgoing NBM pops. Nonetheless, GFS does
show the moisture axis (850-700 MB theta-e ridge) getting strung out
and weakening/drying up as it moves through Lower Michigan.
Outside of the low chance pops late Saturday night into Sunday
morning, dry weather will be the rule early next week as upper level
confluent flow supports another round of good subsidence and strong
high pressure building over Lower Michigan. This high brings a
better chance for temps to fall into the 30s for Tuesday morning.
However, Euro ensemble members are mainly indicating mins aoa 40
degrees.
MARINE...
Widespread rain associated with a cold front will exit southeast of
Lake Erie late this morning. Post frontal shallow cold air advection
along the lead edge of expansive high pressure over the northern
Plains will result in increasing north-northwest winds today.
Available guidance suggests moderate to high probability for wind
gusts of 25 to 30 knots across the open waters of Lake Huron. This
will also help drive hazardous conditions to small craft across the
Lake Huron nearshore waters today. The high pressure system will
expand across the Great Lakes region tonight into Saturday,
resulting in light winds. The rapid eastward departure of this high
by Sunday will drive another frontal system into the region by the
end of the weekend. This front will be moisture starved and
generally weak, limiting weather conditions to just light rain
chances. Its passage will be marked by a veering of the winds from
south to west-northwest. Some uptick in the winds is expected over
Lake Huron within the post frontal cold air advection. Available
guidance indicates the winds remaining below gales.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...None.
Lake Huron...Small Craft Advisory until 10 PM EDT this evening for LHZ421-443.
Small Craft Advisory until 4 AM EDT Saturday for LHZ441-442.
Lake St Clair...None.
Michigan waters of Lake Erie...None.
&&
$$
AVIATION.....CB
DISCUSSION...SF
MARINE.......SC
You can obtain your latest National Weather Service forecasts online
at www.weather.gov/detroit.