St. Clair Shores, Michigan 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

275
FXUS63 KDTX 200357
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
1157 PM EDT Thu Jun 19 2025

.KEY MESSAGES...

- Chance for additional isolated-scattered strong thunderstorms
  Friday and Saturday.

- Record/near record heat Sunday and Monday. High temperatures well
  into the 90s and heat index at or above 100 degrees, with minimal
  relief at night.

- Very warm mid week, with increasing chance of showers and
  thunderstorms.

&&

.AVIATION...

Surface based thunderstorms have about run the course leading up to
midnight leaving a stray elevated shower/storm for the rest of
tonight. Additional convective clusters farther upstream in WI are
expected to also gradually fade while MCS development evolves in the
northern Plains into the upper Midwest. The front stalled across
central Lake Huron and Lower Mi feeds light west wind over the SE Mi
terminal corridor accompanied by pockets of mid and high clouds.
This makes patchy fog possible for a few hours around sunrise
leading into a VFR morning across the region. Some form of MCS
persistence is expected far enough east for at least the decaying
phase to reach SE Mi in the afternoon but is projected east of the
area by Friday evening.

For DTW/D21 Convection... The best chance of thunderstorms occurs
Friday afternoon as activity moves in from the upper Midwest. Trends
will be monitored for strength and intensity forecast refinement in
later updates.

 THRESHOLD PROBABILITIES...

* Low for ceiling at or below 5000 ft late tonight and Friday.

* Low for thunderstorms Friday afternoon.

&&

.PREV DISCUSSION...
Issued at 311 PM EDT Thu Jun 19 2025

DISCUSSION...

Clouds and showers this morning into the early afternoon from our
departing low pressure system has limited temps and instability thus
far. However, the long late June day and developing sunshine,
coupled with 500 MB temps lowering to -15 C as another upper level
disturbance arrives could prove to be sufficient to generate
isolated thunderstorms early this evening with MLcapes 500-1000 J/kg
per RAP (assuming temps reaching into lower 70s). 0-6 KM bulk shear
under 25 knots will limit severe threat, but precip loaded downdraft
strong wind gusts (~50 mph) and hail (<1") look to be in play as wet
bulb zero heights reside just under 10 kft.

Big pattern shift this weekend into early next week, as a strong
upper level ridge builds over the Central Appalachians, with Euro
ensembles indicating 90+ percent probability of 500 MB height
reaching aoa 597 DAM by Monday. Sunday and Monday look to be the
hottest days over southeast Michigan. Otherwise, possible convection
developing during the daytime hours will lead to a lower confidence
forecast on the other days. Frontal boundary hangs around the Great
Lakes region, and the strength to the cap looks to be weakening next
week as the ridge center also looks to be drifting south.

Before we get to the heat wave, upper level trough along the Pacific
Northwest/British Columbia coastline looks to direct a strong
shortwave through Lake Superior Saturday morning. With the steep mid
level lapse rates and southeast Corfidi vectors, there is some
concern an organized MCS could make a run toward southeast Michigan
on Saturday. At the very least, elevated thunderstorms are possible
Saturday morning as ~50 knot jet in the 850-700 MB layer tracks into
Central Great Lakes. MUcapes ramping up through the day, above 3000
J/kg, but dry and warming mid levels should attempt to cap activity
for the afternoon hours. As such, with southwest flow in the low
levels and 850 MB temps reaching aoa 21 C, we should be able to
sneak in our first 90 degree day of the Summer.

Heat and humidity only builds further to close out the weekend, with
temperatures looking to peak out in the mid to upper 90s based on
23+ C 850 MB temps on both Sunday and Monday. With surface dew pts
expected to be in the lower 70s/around 70 degrees, heat indices will
exceed 100 degrees, potentially approaching 105 degrees briefly in
localized spots. Have included the record high temperatures in the
climate section, with the high temperature at Detroit on Monday
(June 23rd) appearing to be the lowest hanging fruit and likely to
be broken. Heat Advisories at the very least will likely be issued
as we get closer, but still potential for extreme heat
watch/warning.

MARINE...

Low pressure is in the process of peeling away from the region this
evening supporting steadily weakening W/NW winds. Lingering showers
(and perhaps a thunderstorm) likewise taper off by late this
evening. Friday through the beginning of next work week is
characterized by a broad ridge of high pressure building across the
central CONUS/Great Lakes. This ridge brings much above normal heat
and humidity throughout that timeframe. There are chances for
thunderstorm complexes to ride atop said ridge into the Great Lakes
offering chances for the central Great Lakes to see continued active
weather.

CLIMATE...

The record highs for Sunday, June 22nd.

Detroit: 98 Degrees (Set in 1988)
Flint:   96 Degrees (Set in 1923)
Saginaw: 94 Degrees (Set in 1966)

The record high minimums for June 22nd.
Detroit: 73 Degrees (Set in 1988)
Flint:   71 Degrees (Set in 1988)
Saginaw: 69 Degrees (Set in 2024)

The record highs for Monday, June 23rd.

Detroit: 95 Degrees (Set in 1923)
Flint:   98 Degrees (Set in 1923)
Saginaw: 96 Degrees (Set in 1923)

The record high minimums for June 23rd.
Detroit: 74 Degrees (Set in 1923)
Flint:   71 Degrees (Set in 2013)
Saginaw: 72 Degrees (Set in 1975)

The record highs for Tuesday, June 24th.

Detroit: 97 Degrees (Set in 1952)
Flint:   95 Degrees (Set in 1934)
Saginaw: 96 Degrees (Set in 1938)

The record high minimums for June 24th.
Detroit: 74 Degrees (Set in 1923)
Flint:   73 Degrees (Set in 1997)
Saginaw: 73 Degrees (Set in 1997)

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

AVIATION.....BT
DISCUSSION...SF
MARINE.......KDK
CLIMATE......SF


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