614
FXUS63 KMQT 100536
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
136 AM EDT Thu Jul 10 2025

.KEY MESSAGES...

- Chances for showers and thunderstorms return Friday and
  Saturday. Otherwise, a mostly dry end of week is expected.

- Seasonable temperatures persist in the Upper Peninsula for
  the work week.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 225 PM EDT Wed Jul 9 2025

Surface ridging overhead has kept the region dry under light
northerly flow. This has sustained overcast skies in the west half
and south half of the eastern counties, with what appears to be a
diurnal boost in coverage this morning, and temperatures in the 50s
and low 60s by Lake Superior and 60s to low 70s elsewhere. Suspect
cloud cover could stick around for the next hour or so, but believe
a trend toward clearing skies will occur this afternoon and evening.
Mostly clear skies tonight will allow temperatures to fall into the
50s, with interior areas dipping into the mid to upper 40s.

High pressure sticks around Thursday, supporting another dry day.
Temperatures look to warm into the low to mid 70s by Lake Superior
and upper 70s to low 80s elsewhere. Given the increasing southerly
flow, afternoon lake breeze off Lake Superior isn`t expected to push
inland far. A more mild night is expected Thursday night thanks to
increasing moisture ahead of the next system. Overnight temperatures
look to fall into the 50s, with low to mid 60s far west.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Issued at 225 PM EDT Wed Jul 9 2025

Beginning Friday, mid-upper ridge axis will lay through Upper
Michigan, with a series of shortwaves embedded within split stream
flow stream upstream over the Central and Northern Plains. Various
placement of previous night MCVs are apparent in the different
deterministic packages, which supports my initial uncertainty in the
timing of the key features for Upper Michigan. Although 12z guidance
appears to have produced a better consensus which overall looks
to pull a warm front or the attendant surface low through the
forecast area Friday afternoon or overnight. This while the mid-
level shortwave to the west moves from the Dakotas into
Minnesota/western Lake Superior. This main shortwave begins to
take on a negative tilt, which might absorb the original
low/shortwave. 6z and 12z guidance is unclear if this will
actually take place overhead or downstream in northern Ontario.
Regardless though, the cold front will help push the surface low
through the region Saturday and Saturday night. While questions
of the timing and location of the initial features exists,
showers, potentially mixed with thunderstorms should be
expected. Given the temporal clarity of the initial timing of
precip, instability/shear may be present over the region, which
could support stronger storms late Friday. DCAPE values suggest
an isolated strong to severe wind threat, but model soundings
show light background winds upwards of 25k ft, suggesting this
potential is low (<25%). Guidance also suggests potential for
mid-level lapse rates increasing to ~7C/km, which may be enough
to support hail should a stronger updraft get going. Showers and
storms will press through the region overnight while the cold
front moves in from the west. Given the questions about phasing
and the timing of the initial showers/storms, its unclear if
precip will occur all day Saturday, or be mainly limited to the
afternoon/evening hours ahead of the front.

From there, another shortwave migrates through the region Sunday
evening and overnight while surface high shifts from the Upper
Midwest to the Lower Great Lakes. The high looks to keep the region
mostly dry Sunday, but a line of showers may accompany the wave late
Sunday night/Monday morning. A deep trough moving through the
Canadian Prairies and a shortwave lifting northeast from the Central
Plains will shift toward Upper Michigan on Monday. There are notable
timing differences in the model suites regarding these and whether
or not they`ll phase overhead next week. Right now the main window
for precip associated with these features focuses on Tuesday to
Wednesday. Daytime highs each day look to climb into the 70s to mid
80s and with overnight lows dipping into the 50s and 60s.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 135 AM EDT Thu Jul 10 2025

Primarily VFR conditions are expected at all TAF sites through the
duration of the 6Z TAF period as high pressure holds over the Upper
Great Lakes. The one exception to this is at SAW when some MVFR
BR/FG development is anticipated early this morning. That said,
guidance has slightly backed off on FG potential, so IFR vis or
lower is less likely than the previous fcst package (now ~25%
chance or less). Some MIFG is possible at IWD, but no vis
restrictions are expected so mention was left out of the TAF for
now. Otherwise calm winds this morning increase out of the S at
IWD/SAW and E at CMX to around 6-8 kts for this afternoon.

&&

.MARINE...
Issued at 225 PM EDT Wed Jul 9 2025

Winds generally remain generally ~15 kts or less through the
remainder of the work week as weak high pressure traverses the Great
Lakes. However, a couple of disturbances move through the region
Friday into the weekend. Thus, we can expect showers and
thunderstorms to form from west to east across the lake from Friday
through Saturday. In addition, we could see winds increase to around
15-20 knots from the southwest on Saturday, persisting into Sunday
before falling back into Monday. Expect a brief reprieve from
convection Sunday before additional storms potentially move in with
a Clipper system next Sunday night through Monday.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.

&&

$$

SHORT TERM...JTP
LONG TERM...JTP
AVIATION...Jablonski
MARINE...LC