346
FXUS63 KMQT 081147
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
747 AM EDT Mon Jun 8 2026

.KEY MESSAGES...

- Showers and thunderstorms return to the western half today,
spreading east tonight into Tuesday.

- Temperatures trend hotter this week, with widespread 90s possible
mid to late week.

- Strong to severe thunderstorms are becoming more likely on
Wednesday. Continue to monitor the forecast for additional details.

&&

.DISCUSSION...
Issued at 340 AM EDT Mon Jun 8 2026

Early morning GOES water vapor imagery and RAP analysis places the
axis of a stout upper level ridge just east of the UP, extending
from eastern Ontario down through Lake Huron and into the Ohio River
Valley. A shortwave trough is riding up the western side of the
ridge into the Upper Mississippi River Valley, with associated
showers and a few embedded thunderstorms noted upstream over WI and
MN on regional radar imagery as broken mid level cloud cover streams
into the UP ahead of this activity. Expect these showers to start to
spread into the far western UP after daybreak as the shortwave
continues to lift northward towards the Upper Great Lakes.
Isentropic ascent in tandem with more than ample moisture (PWATS
1.75-2", near the max of NAEFS PWAT climo for this time of year)
will be the driver for scattered shower/t-storm development that
encompasses the western half of thew UP through this afternoon and
then slowly spreads east tonight into Tuesday. CAM ensemble 24 QPF
spread ending Tuesday afternoon still suggests mean amounts around
0.25", though given the scattered nature of precip, high PWATs, and
meager MUCAPE, thinking that the precipitation footprint will not be
so uniform across the area. Areas that receiving multiple rounds of
showers with embedded thunderstorms could easily collect upwards of
1-1.5". No severe storms are expected at this time given meager
shear and instability. Precip should largely clear the area by
Tuesday afternoon, leaving room for a brief period of quiet weather
save for lake breeze driven afternoon precipitation potential.

A more potent shortwave is forecast to lift through High Plains on
Wednesday, developing a strong surface cyclone that works into
Ontario through the afternoon, placing much of the Upper Midwest and
Northern Great Lakes in a ripe warm sector. Ensemble joint
probability of at least 1500 j/kg of sfc based instability and deep
layer shear >30 kts reaches 40-50% across the western UP and Lake
Superior Wed PM, suggesting possible strong to severe storms capable
of producing large hail and gusty winds. Exceptionally high PWATs
also suggest the potential for flash flooding. At this time, SPC
continues to highlight a severe risk for most of MN, WI, and the
western UP as we move into Day 3. Outdoor recreationists should
continue to monitor forecast trends!

In addition to the increased moisture, warm temperatures, possibly
the warmest experienced so far this early summer, are expected into
the midweek. The NBM continues suggesting a high chance (60-90%) of
surface temps exceeding 90F across the interior west and central
Wednesday/Thursday. However, these temperatures may be inflated by
the ensemble`s bias correction, which was been warmer than observed
recently. Non-bias corrected ensembles such as the LREF, comprised
of other global ensembles, suggests a low <30% chance for sfc temps
reaching 90F this far north. Regardless, its becoming increasingly
likely that the warmest (and most humid) airmass of the warm season
so far is ahead this week, so individuals with heat sensitivity
should prepare as necessary!

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 747 AM EDT Mon Jun 8 2026

Low pressure will track through the region today bringing increasing
cloud cover and precipitation chances from west to east. This will
result in VFR conditions this morning eventually deteriorating to
MVFR at IWD and CMX later this afternoon. IFR conditions will be
possible at times by afternoon as showers with embedded
thunderstorms spread across the western UP. Will handle -TSRA
chances with PROB30s beginning after 18z at IWD and 22z at CMX. For
SAW, VFR conditions are expected through the afternoon, then
conditions will deteriorate after 00z Tuesday as showers move into
the area, with PROB30s for -TSRA after 02z Tue. Expect conditions to
go down to IFR at all terminals tonight after 06z Tue.

&&

.MARINE...
Issued at 340 AM EDT Mon Jun 8 2026

Going forecast remains on track with overall light winds <25 kts
lake wide through the first half of the week. Could see a few gusts
getting up around 25 kt on the east side of the Keweenaw this
afternoon, but thinking these should be sparse enough in coverage
and with wave heights only building to around 1-3 feet to forego any
headlines today. Some strong to severe thunderstorms are possible
Wednesday P.M., largely across the western half. Continue to monitor
the forecast for ongoing trends and updates. The second half of the
week is slated to be a bit windier as forecast guidance continues to
trend several systems into the Northern Great Lakes, bringing
additional chances for showers and thunderstorms as well as periods
of winds >25 kts.

&&

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

&&

$$

DISCUSSION...BW/CB
AVIATION...CB/NL
MARINE...BW/CB