506
FXUS63 KDTX 051801
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
101 PM EST Fri Dec 5 2025

.KEY MESSAGES...

- Frigid wind chills tonight falling in the negative single
  digits. Low teens wind chills Friday afternoon.

- Below normal temperatures persist this weekend and into next week.

- The next chances for light snow will be Friday night and Sunday.
  Sunday holds a 50% chance to exceed 1 inch.

&&

.AVIATION...

Ceilings in the 4-5kft range are encroaching on southeast Michigan
this afternoon with expectation for similar ceilings to reach the
southern metro terminals later this afternoon and tonight.
Conditions should remain VFR through the remainder today with trends
towards MVFR arriving tonight ahead of a cold front. Scattered gusts
towards 20 knots will remain possible this afternoon with a
sustained wind of around 10 knots holding through tonight. A few
flurries and possibly some mixed wintry precipitation will be
possible mainly across FNT and MBS tonight and tomorrow morning.
Precipitation expected to be very light and will maintain TEMPO
groups for snow showers around the more likely time to see this
precipitation. Winds veer more westerly to around 10 knots towards
the early afternoon tomorrow.

DTW THRESHOLD PROBABILITIES...

* Medium for ceiling at or below 5000 ft this afternoon. High
  tonight.

&&

.PREV DISCUSSION...
Issued at 351 AM EST Fri Dec 5 2025

DISCUSSION...

The 00Z DTX RAOB recorded a PW value of .10", a daily record, which
has maintained virtually clear skies overnight under calm to very
light winds. This idealistic setup for efficient radiational cooling
under snow covered grounds have lead to an anomalously cold start to
the morning with temperatures ranging in the single digits across SE
MI. Very modest warm air advection this afternoon under southerly
flow will have temperatures only warming up into the mid 20s. Winds
gusting around 15 mph will maintain wind chills in the teens through
the daylight hours. The advent of upper-level clouds will hold
overnight temperatures in the upper teens to low 20s overnight.

A weak prefrontal trough and passage of a cold front does bring the
chance for some wintry precipitation overnight through Saturday
morning, but the weaker forcing within the dry environment precludes
any meaningful accumulation. A dusting of snow accumulation will be
possible across SE MI, most favorable over the northern third of the
cwa (north of M59) where slightly better moisture resides. Given
moisture quality issues, the shallow moisture depths will likely
reside just shy of the dgz, nearing - 10C. While ice nucleation is
still likely with these cooler temperatures, there will be low chance
for some periodic freezing drizzle. Forcing along the cold front,
projected to move through in the mid morning hours into the early
afternoon, can briefly elevate moisture heights back into the dgz and
will be capable of producing a quick dusting of snow.

Dry air filters in the wake of the front as the brunt of the polar
airmass holds north of the state, allowing temperatures to rise into
the low 30s for a high Saturday. Attention will then turn to the
next potential accumulating snow event which will derive from a
clipper system which is projected to arrive across the Plains into
the Midwest late Saturday night before spreading  across the Great
Lakes region by Sunday morning. System relative isentropic ascent
will be maximized through the mid-levels between 700 to 500 mb which
will allow for light snow development to overspread across the Ohio
Valley into Michigan. A dusting, up to two inches of new
accumulation will be possible pending how well the system sustains
intensity as it travels into the region.

One possible scenario leading to lesser snow amounts will be the
speed at which an arctic high pressure drops down from the plains
which will have the ability to hold the better moisture south of the
state line as dry air filters in. The latest EPS solution favors this
scenario, bringing probabilities to see an inch of snowfall to 15%
or less. NBM probabilities which encapsulates a larger set of
ensembles holds chances around 30%, a decreasing trend from 12 hours
ago. Outside of the northern Thumb which will hold onto lake effect
snow chances in the wake of the low pressure, the arctic high will
set up over the Great Lakes bringing dry conditions late Sunday into
Monday. This also brings well below normal temperatures to start the
next week with highs in the 20s and lows in the single digits to
lower teens.

MARINE...

Pressure gradient is beginning to tighten early this morning as the
next low pressure system starts moving into Ontario with a cold
front draped through the Midwest. The cold front will not sweep
through until early Saturday which will lead to another round of
increased southwesterly winds early this morning through early
Saturday. Another round of Small Craft Advisories for Saginaw Bay
have been issued as southwesterly winds again increase to around 30
knots. Could see a few gusts to 35 knot gales over central Lake
Huron Friday, but should be isolated enough to avoid mentioning
gales in the forecast at this point. Guidance did pretty well with
the winds the last couple days with both southwest and northwest
flow, which lends to increased confidence with this next event.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...None.
Lake Huron...Small Craft Advisory until 4 AM EST Saturday for LHZ421-422-441.

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

$$

AVIATION.....AA
DISCUSSION...AM
MARINE.......DRK


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