596
FXUS63 KMQT 272314
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
714 PM EDT Fri Jun 27 2025

.KEY MESSAGES...

- Rain showers and thunderstorms lift into Upper Michigan
  Saturday evening and Saturday night. Some strong storms can`t
  be ruled out Saturday evening across the west half of Upper
  Michigan and Lake Superior.

- There is a slight chance of strong to severe storms Sunday
  afternoon and evening. Should organized storms occur, large
  hail and damaging winds will be the main severe weather
  hazards.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 215 PM EDT Fri Jun 27 2025

Surface low and its associated warm and cold fronts slowly moved
through Upper Michigan this morning, producing mostly cloudy skies
and pockets of light rain. As of this writing, the warm front is
pressing into eastern Upper Michigan with the cold front extending
southwest through the western interior. Lingering morning fog
largely mixed out behind the warm front, but pockets of fog are
still being observed ahead of the warm front and cooling behind the
cold front have support pockets in the west and Keweenaw. Mostly
cloudy skies with the aforementioned features have supported temps
in the 50s and 60s mostly, with 70s being observed within the warm
sector across the south-central.

For the rest of today and this evening, the surface low will lift
northeast into Ontario while the mid-upper level shortwave presses
into the west atop a surface high. The fronts will follow the low,
exiting the region this evening. For the most part, the west half
should continue cooling while the east and maybe the south-central
warms a little more thanks to the transiting warm sector. Drizzle
and some pockets of fog will continue to be possible, mainly where
terrain is enhancing flow across the west/Keweenaw and north-central
and in the east along the transiting cold front. Tonight, conditions
should be mostly dry with lows near 50 to the mid 50s. Additional
fog is expected to develop, with some potential for less than 1 mile
visibilities, mainly across the west half. Latest HREF suggests
probability of such being >50%. Saturday, surface ridge axis will
press through, supporting mostly dry conditions under mostly sunny
skies. Daytime temps look to warm into the 70s by the
lakeshores/interior, but low 80s interior west.

Late in the afternoon upstream, a warm and cold front will approach
the Great Lakes. Instability and a low level jet will support
elevated thunderstorms developing across Minnesota. These will press
eastward through the evening and overnight as the fronts approach
the region. There are still some questions about how widespread
convective activity will be ahead of and along the approaching
fronts. General thought is that showers and thunderstorms will press
into Upper Michigan/Lake Superior along the warm front in the
evening/overnight, with some potential for some strong storms in the
evening across the west half before instability wanes. Expecting the
remnants to continue pressing eastward through the forecast area
overnight.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Issued at 215 PM EDT Fri Jun 27 2025

Long term period begins Sunday with sprawling mid-upper level
ridging stretching across most of southern CONUS, with a trough
slowly lifting north along the southern California coastline. Across
the northern tier, near-zonal flow with two troughs embedded within
are noted among the deterministic suite. The first and downstream
one looks to push offshore of Maine through the day and the second,
and more notable trough, stretches south from Manitoba into the
Northern Plains. Ahead of this, a few different shortwaves are
expected, with the initial wave pressing into Upper Michigan by
Sunday afternoon. There are still timing and positional differences
among the deterministic suites for the accompanying warm and cold
fronts, but the general consensus is for an exiting warm front Sunday
morning stretching eastward/southeastward across the Keweenaw into
central/eastern Upper Michigan with the cold front progged to press
west to east through the forecast area in the afternoon into the
overnight hours. As the warm front pushes east through the morning,
lingering showers and thunderstorms in our forecast area should
follow. Through the day Sunday, very strong instability,
characterized by MUCAPE growing to 2000-3000j/kg within the warm
sector, under persistent southwesterly 20-30kt 925-0850mb flow will
help support an environment capable of strong to severe
thunderstorms ahead of the cold front by afternoon. Main area of
development looks to be the central third but scattered
showers/storms may develop across the east half as well. Deep layer
shear isn`t very impressive, but steepening mid-level lapse rates to
7-8C/km and DCAPE potentially growing to 1000-1500j/kg suggests
large hail and strong to damaging wind hazards in any organized
storm. Precip will press eastward overnight, potentially lingering
into Monday morning across the east.

Surface high pressure will build in afterwards that`ll linger
through a majority of the week. However, the mid-upper level trough
axis associated with Sunday`s precip will press through Monday with
another shortwave diving southeast into the Upper Great lakes
Tuesday evening. These may help support additional rounds of
afternoon/evening showers or storms each day, particularly Monday
associated with the slow to exit cold front in the east. At the
moment, instability is lacking, so strong to severe storms aren`t
expected. Surface ridge axis presses through Wednesday, which looks
to keep things dry.

Southerly flow will support a warm and humid day Sunday, with
widespread 80s and dewpoints near 70. We`ll cool afterwards with 80s
Monday and upper 70s to low 80s through at least mid-week. Overnight
lows Sunday night will be mild, with widespread 60s. Monday night
and onward, overnight lows mostly look to be in the 50s.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 711 PM EDT Fri Jun 27 2025

While IWD has scattered out to VFR now, MVFR cigs still hold on at
SAW and below airport min conditions at CMX this evening. With FG
developing across the TAF sites this evening, we could develop near
airport min conditions across SAW and IWD tonight. By Saturday
morning, though, expect the skies to eventually clear out to VFR
across all the TAF sites after sunrise.

&&

.MARINE...
Issued at 215 PM EDT Fri Jun 27 2025

Northwest winds around 20 kts will fall below 20 kts this evening
across the east with southwest to west winds below 20 knots across
the west and central tonight as high pressure builds into the
region. Waves will fall below 3 ft by tonight. Winds and waves then
remain mostly calm as only weaker pressure systems affect the lake
for the weekend into next week, though periodic thunderstorms may
occasionally be over the lake, with the highest chances being late
Saturday night through Sunday evening.

&&

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

&&

$$

SHORT TERM...JTP
LONG TERM...JTP
AVIATION...TAP
MARINE...PK