152
FXUS63 KDTX 121040
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
640 AM EDT Thu Jun 12 2025

.KEY MESSAGES...

- Showers slide across areas north of I-69 this morning. An isolated
thunderstorm is possible this evening west of US-23.

- Cooler with periods of showers and storms Thursday through the
weekend.

&&

.AVIATION...

Jet entrance region driven 850-700mb fgen has resulted in a corridor
of high based shower activity early this morning. Dry air in the
lower troposphere brings a high likelihood for VFR conditions today
and tonight. Thunderstorm potential is expected to remain across
southwest Lower Michigan along a stalled frontal boundary. Winds are
expected to be out of the north or northeast leading to northeast
flow operations at times.

For DTW/D21 Convection...There is a low chance <20 percent for
isolated convection across the airspace today.

THRESHOLD PROBABILITIES...

* Low in thunderstorms Thursday.

&&

.PREV DISCUSSION...
Issued at 307 AM EDT Thu Jun 12 2025

DISCUSSION...

Advertised cold front is in the process of gradually sagging south
through southern lower MI early this morning with little fanfare
thus far overnight. This is changing around discussion time as a PV
anomaly coming out of the northern Plains slides along the boundary
into SE MI. Remnant convection associated with this wave works
across the northern portions of the CWA (north of I-69) through the
remainder of the morning. With the arrival window falling in the
diurnal minima of instability, little to no thunder chances are
expected from these showers. Wave kicks east of the region by
afternoon tapering off any lingering light showers. Frontal boundary
stalls near the state border setting up an instability gradient
across the far southernmost portions of the state (especially SW
lower) by late afternoon-evening. The majority of the CAMs attempt
to initiate convection along this feature by early evening, though
to differing degrees ranging from only a couple isolated cells
confined to our west (ie 00Z ARW) to a scattered storms that drift
into southwestern CWA counties given the still west-southwest low-
mid level wind field (ie 00Z HRRR). Without a strong forcing
mechanism, overall confidence remains relatively low so have
maintained the running 20-25% PoPs.

Another northern Plains shortwave arrives over the northern Great
Lakes Friday partially lifting the stalled front back north over the
course of the day. Better rain chances still looking to occur on the
elevated portion of the front over northern lower MI given the
placement of the parent wave leading to limited rain chances
locally, focused over the northern half of the area. Closed mid-
level low lifting out of the southern Plains begins to phase with
the northern wave late Friday-Saturday offering the best chances for
scattered to numerous showers, and perhaps a thunderstorm near the
state border, for the southern half of SE MI. This mid-level trough
begins to sink back southeast by Sunday pulling associated shower
activity just south of the area over Ohio. While a stray shower or
two could lift north of the state line, the majority of the area
sees a return of dry weather as weak surface high pressure builds in
from the north.

MARINE...

A frontal boundary settles into the southern Great Lakes today as
high pressure builds across Ontario. The weak gradient associated
with this high maintains light winds predominantly out of the north.
Diurnal wind enhancement will occur over Saginaw Bay this afternoon
where northeast flow briefly increases to around 20 kt. The high
shifts east toward Quebec on Friday with northeast wind increasing
to the 15 to 20 kt range over all of Lake Huron. Showers and
embedded thunderstorms will spread across the lakes Friday into
Saturday but severe weather is not anticipated at this time. High
pressure builds directly across the lakes on Sunday to bring a
drier end to the weekend.

&&

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

$$

AVIATION.....CB
DISCUSSION...KDK
MARINE.......TF


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