Expert Forecast Opinion

151
FXUS63 KDTX 051143
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
643 AM EST Thu Mar 5 2026

.KEY MESSAGES...

- Areas of fog with pockets of light rain and drizzle this morning.

- Showers increase coverage this afternoon and evening. Elevated
thunderstorms possible mainly south of I-94.

- Milder temperatures move into the area Friday-Saturday with
daytime highs in the 60s.

- Showers and thunderstorms are possible Friday night and Saturday
ahead of a cold front Saturday afternoon.

&&

.AVIATION...

A warm front remains draped across Ohio with very moist
northeasterly flow keeping the airmass below the inversion saturated
resulting in low stratus and fog. The IFR/LIFR CIGs and VSBYs have
been a little slow to lift into the area but it looks like they are
making steady progress northward early this morning. Should be most
if not all of the forecast period before we start to recover toward
MVFR. Could see pockets of drizzle early in the day before the next
wave lifts over the front producing the next round of widespread
rain. Front remains to the south tonight leading to another round of
fog.

For DTW...LIFR stratus has spread over the area and should waver
very little through the period. Drizzle will be possible over the
next few hours before the next round of widespread rain passes
through during the afternoon. Another round of sub 1SM fog is likely
tonight with the front remaining to the south.

DTW THRESHOLD PROBABILITIES...

* High for ceilings at or below 5000 ft through Friday morning.

* Moderate for ceilings and visibilities below 200 ft and 1/2SM
through this morning and again tonight.

&&

.PREV DISCUSSION...
Issued at 405 AM EST Thu Mar 5 2026

DISCUSSION...

Lead wave of 925-850mb theta-e advection led to a flare up in rain
earlier this morning, but coverage and intensity has since waned as
mid-level dry slotting moves overhead. Upstream observations suggest
a lowering stratus deck possibly transitioning to dense fog by
daybreak, especially toward the Ohio border where rain ends the
earliest this morning. Will be monitoring visibility trends closely
for fog headline potential this morning. Otherwise, it will be a
chilly and damp start to the day as current temperatures are only in
the mid 30s.

Brief dry spell this morning will be quickly followed by another
round of rain this afternoon-evening as a compact shortwave shears
across the northern Ohio Valley. The wave is very well-defined on
satellite imagery this morning over southern Iowa, and SPC
mesoanalysis highlights a steep plume of mid level lapse rates (8
C/km) associated with it. Models are very aggressive with ascent,
generating omega values near -50 ubar/s for the local area. This
forcing reaches the doorstep of SE Michigan between approximately 16-
21z (11a-4p), ramping rain chances back up toward 80-90% as the wave
interacts the with back edge of the Gulf moisture transport. The
impressive synoptic ascent and marginal elevated instability should
be enough to support thunder, especially toward the state line
nearest to the cold core (-20 C). Most of SE Michigan is in a
General Thunder designation by SPC. Models confidently keep the
surface low and warm front south of the state line, holding
temperatures in the 40s while keeping convection elevated. While
weak instability will generally limit updraft strength, cannot rule
out hail production given the cold thermal profiles and steep lapse
rate environment (weak signal noted just to our south/west in both
the 00z and 12z CSU-MLP day 2 severe hail probabilities).

Mid-level dry slotting shuts off precipitation chances tonight, but
the stubborn inversion holds firmly in place in the 1.0-3.0 kft agl
layer. Trapped moisture once again introduces dense fog/drizzle
potential Friday morning, as 700-500mb dewpoint depressions approach
40 C indicating the very dry airmass aloft.

Major pattern shift then expected Friday into Saturday as Pacific
troughing ejects into the Plains. Plenty of vertical depth to the
synoptic forcing with this system, while strengthening southwest
flow draws gulf moisture northward. Strong 45-50 knot low level jet
surges into northern Michigan Friday afternoon, introducing elevated
instability as the low levels moisten. The warm front will initially
struggle to overcome to resident airmass and marine layer, but will
eventually overtake it Friday night. Temperatures approach 60
degrees by sunset, and warm a few more degrees after dark. The
inversion looks to stay in tact for most of the night, keeping both
the wind field and unstable airmass elevated. The background
environment Friday night will have all the pieces for organized
convection and will just be dependent on forcing, most likely the
low level jet which in latest model cycles takes on a northerly
track over the Saginaw Valley/Thumb. SPC Day 2 hail probabilities
are right up against us Friday night.

The more widespread convection comes Saturday as a strong cold front
sweeps across lower Michigan. Convection is expected to organize
linearly along the front given the secondary surge of southwest
winds just ahead of it. Timing of the front will play a big role in
whether these storms can become rooted in the surface. SPC has
designated a Marginal Risk for eastern portions of the cwa Saturday,
where surface destabilization is most likely. Destabilization will
also determine wind gust potential for Saturday, possibly tapping
into the 50-60 knot low level jet core. Breezy southwest flow and
highs in the mid to upper 60s create a mild day despite the rain
chances. Seasonable warmth then stays within reach through early next
week with periods of unsettled weather continuing as several waves
traverse across Canada and high pressure anchors over the Atlantic.

MARINE...

Areas of dense fog early this morning, particularly over the
southern Great Lakes, give way to widespread showers (potentially an
isolated thunderstorm) and strengthening east-northeast winds as low
pressure tracks near Lake Erie. Strongest wind occurs over the
northern and central portions of Lake Huron where gusts between 20-
25kts are forecast. Closer proximity to the weak low center keeps
wind 20kts or less over the southern half of the region.

Brief dry period sets up early Friday before another low lifts out
of the Plains and over the northern Great Lakes. Attendant warm
front crosses Friday night shifting winds from the southeast to
southwest by early Saturday. While flow aloft strengthens post-
front, a much above normal airmass will maintain strong thermal
stability over the lakes which is expected to cap gusts below 30kts,
save for immediate lakeshore waters. Scattered showers and a few
thunderstorms are possible with the warm front though better
coverage arrives daytime Saturday as the system`s cold front crosses
the central Great Lakes. There is a couple hour window
along/immediately following the front where west/west-northwest
gusts could near entry-level gales. Otherwise, southwesterly flow
and milder air return by Sunday in response to low pressure tracking
across northern Ontario.

HYDROLOGY...

Rounds of showers are expected today, with embedded thunderstorms
possible south of I-94 this afternoon. Storm total rainfall amounts
are generally expected to range between 0.25" to 0.75", although
locally higher amounts are possible if any thunderstorms develop.
Additional showers and thunderstorms are expected Friday into this
weekend. Potential impacts include rises on area rivers and ponding
of water on roads.

CLIMATE...

The record highest minimum temps for Saturday, March 7th.

Detroit: 47 Degrees (Set in 2012)
Flint: 49 Degrees (Set in 2012)
Saginaw: 49 Degrees (Set in 2012)

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...Dense Fog Advisory until 10 AM EST this morning for MIZ082-083.

Lake Huron...Dense Fog Advisory until 7 AM EST this morning for LHZ421-422-
441>443-462>464.

Lake St Clair...Dense Fog Advisory until 10 AM EST this morning for LCZ460.

Michigan waters of Lake Erie...Dense Fog Advisory until 10 AM EST this morning for LEZ444.

&&

$$

AVIATION.....DRK
DISCUSSION...MV
MARINE.......KDK
HYDROLOGY....MV
CLIMATE......MV


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at www.weather.gov/detroit.