874
FXUS63 KDTX 250855
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
355 AM EST Sun Jan 25 2026

.KEY MESSAGES...

- A Winter Storm Warning is in effect for Monroe County, and Winter
Weather Advisory along and south of the M 59 corridor as well as the
eastern Thumb.

- Light snow chances exist both Tuesday and Wednesday. Fluffy snow
accumulations of up to 2 inches will be possible each day.

- Very cold conditions continue next week with wind chills
occasionally dipping to 10 to 15 below zero.

&&

.DISCUSSION...

Coupled upper level jet dynamics with strong anticyclonic curvature
to the forward +180 kt streak will guide 850-700m baroclinic
wave/circulation through the northern Ohio River Valley while
locking in the northern fringes of the deformation axis over
Southeast Michigan today. Much of the forecast reasoning provided in
earlier discussions remains valid. The inherited grids were largely
maintained with a few upward revisions to the PoPs. As previous
discussions have stated, the gradient of the liquid equivalent in
close proximity to the area presents a challenge. Survey of the
25.00z NWP with context provided by the 5.0 NBM snowfall percentiles
suggests no substantial trends or changes to the storm total QPF for
much of Southeast Michigan. Overall, thinking stands at .25 to .40
inch range event total. Limitations on the upper end for snowfall
amounts, are compromised ice crystal microphysics with more of a
fine sugar type habit thus far and snowfall ratios that are
forecasted at/around 14:1. Forecast soundings show relatively high
stability for much of today between a deep 2.5 and 20.0 kft agl
which suggests the system here locally is really going to rely on
forced ascent with any true upright warm frontal structure well to
the southeast of Toledo. Supersaturation with respect to ice is very
deep and the overall forecast and messaging is in good shape. Storm
total snowfall of 5-8 inches for Monroe County, 4-7 inches for
Lenawee, Washtenaw, and Wayne, and 2-4 inches with isolated 5 inches
amounts along the M 59 corridor. In-house timed lagged ensemble data
suggests very little potential to reach inch per hour rates and so
additional warning upgrades were made.

The one significant change to the forecast was to expand the Winter
Weather Advisory for Huron and Sanilac counties in effect until 10am
Monday. Raw output of Hi resolution CAMS suggests lake effect
banding will push into and swing through eastern sections of the
Thumb in vicinity of the Lake Huron shoreline. There is uncertainty
in timing, but guidance suggests the potential between 03-14z
Monday. 00z runs of the HRRR, ARW, and MPAS all are fairly bullish
on QPF amounts over Huron and Sanilac Counties. For posterity, there
is a very lean QPF signal in the both the AIGFS and ECMWF AIFS.
Forecast soundings show convective heights rising to 8.0 kft agl
with UVV signal intersecting the Dendritic Growth Zone. For
messaging, snowfall amounts of 2 to 5 inches will be possible.

The big narrative for the upcoming week remains the continuation of
the below normal temperatures Winter pattern. Current guidance
supports forecasted Windchill values of -10 to -17F for Tuesday,
Wednesday and Thursday mornings. Refinements will be made in the
coming days as conditions will obviously be dependent on wind
forecasts and the expected cloud cover. Windchill or Cold Weather
Advisories may be needed at some point. Highs throughout the weak are
expected to reach the teens above zero, which is approximately 10 to
15 degrees below normal.

The other item to address is the potential for light snow during
each of the days Tuesday and Wednesday. Current offered guidance is
extremely lean on both PoPs (only a chance) and snow amounts. Up to
2 inches of snowfall appears possible/reasonable with very high
liquid to snow ratios and very low QPF. Dynamics for Tuesday will be
tied to direct absolute vorticity advection from amplified
shortwave, while dynamics Wednesday appears arise from thermal
surface troughing developing under a strong polar vorticity trough
aloft.

&&

.MARINE...

Light winds hold through the day as a strong high pressure departs
into into Quebec. Light snow to continue across the southern Great
Lakes as an expansive low pressure winter storm system moves through
the Appalachia region. Embedded lake effect snow bands will also be
likely through central and southern Lake Huron into Monday, where
some rapid reductions in visibility will be possible. Cold air is
reinforced within the wake of this low across the Great Lakes early
next week, which will bring the return of elevated wind gusts
through the midweek period.

&&

.PREV DISCUSSION...
Issued at 1205 AM EST Sun Jan 25 2026

AVIATION...

Conditions will gradually deteriorate as snowfall spreads further
north with time through the morning reaching MBS by mid-late morning.
Low VFR ceilings with light snowfall precedes the arrival of MVFR
CIGs and VSBYs before the main event unfolds across southeast
Michigan terminals between 11Z and 23Z. Heavier snowfall has been
trending earlier bringing solid IFR to LIFR conditions to the Detroit
terminals by at least 16Z, if not slightly earlier, that then last
through the afternoon. IFR conditions also expected to reach up to
FNT for a period by this afternoon as well. The higher snow
accumulation will reside across DTW airspace with up to 4 to 6 inches
of accumulation and 1 to 3 inches up to FNT. Winds to around 10
knots will slow back from the east to the north as the low pressure
system passes south of the state. Heavier snow will begin to taper
off towards 00Z and after with improvements in visibility while
low ceilings linger.

For DTW...Main window for accumulating snowfall will be focused
between 11Z Sunday morning to 23Z Sunday evening with peak snowfall
rates of a quarter to a half inch per hour between 16Z and 23Z. IFR
conditions are expected with periods of LIFR during the peak of
snowfall rates. Snow accumulations most likely in the 4 to 6 inch
range with lower probability to exceed 6 inches.

 DTW THRESHOLD PROBABILITIES...

* High for ceilings aob 5000 through Sunday.

* High in precipitation type of snow.

* Medium in ceilings of 200 ft or visibilities of 1/2SM in falling
  snow after 16z Sunday.


&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...Winter Weather Advisory from 9 AM this morning to 10 AM EST Monday
     for MIZ049-055.

     Winter Weather Advisory from 9 AM this morning to midnight EST
     tonight for MIZ063-068>070.

     Winter Weather Advisory until midnight EST tonight for MIZ075-076-
     082.

     Winter Storm Warning until midnight EST tonight for MIZ083.

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

$$

DISCUSSION...CB
MARINE.......AM
AVIATION.....AA


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