841
FXUS63 KMQT 070705
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
305 AM EDT Wed May 7 2025

.KEY MESSAGES...

- Cooler and breezy today.

- Cooler conditions linger Thursday, before warming again Friday.
Warm and dry conditions expected through the weekend.

&&

.SHORT TERM /THROUGH THIS AFTERNOON/...
Issued at 305 AM EDT Wed May 7 2025

Mid-upper level ridge axis has shifted through the region tonight
while a weak shortwave presses through Ontario. At the surface, a
cold front has pressed through the region with some surface
troughing extending northwestward over Lake Superior. Overall, dry
air has prevailed with the frontal passage and cloud cover has
mostly been confined to Lake Superior and near it`s lakeshore.
Overnight temps have mostly been observed in the 40s across the
area. Additional cooling tonight may bring lows into the 30s across
the north half and near 40 for most interior spots across the south
half.

A mid-level trough will press through the area today, allowing for
further cooling aloft and continuous northerly surface flow.
Together, these will help support a cool day for Upper Michigan.
Daytime highs look to peak in the 40s in the north half and mid to
upper 50s south half. Cooler air overhead and clear skies will also
enable stronger winds aloft to mix down to the surface. Gusts near
20-25 mph can`t be ruled out at least into the evening hours.

&&

.LONG TERM /TONIGHT THROUGH TUESDAY/...
Issued at 305 AM EDT Wed May 7 2025

Main point of interest for our forecast area in the extended period
will be continued above normal temperatures and mostly dry
conditions. The pattern will evolve in such a way that ridging holds
over the region a majority of the time. This will support mostly
clear skies and effective daytime mixing. Save Thursday and
Saturday, a warmer than normal airmass will hold over the region.
Together the main concern these warmer days be the resultant drops
in daytime relative humidities.

Beginning tonight, upstream mid-level ridge axis will slowly shift
eastward, gradually shifting into the region Thursday. While this
will help sustain seasonally cool temperatures over the region
Thursday, it will also help advect a very dry airmass over the area.
Despite temperatures only peaking in the upper 40s to mid 50s by the
lakeshores and 60s inland, daytime mixing will be able to plunge RH
values into the low 20s to teens for most areas removed from the
immediate lakeshores. 0z HREF suggests 100% chance of falling below
25% RH in the interior west half and pockets of 50-60% chance in the
interior east half. The same guidance suggests near 30% of falling
below 20% in the interior west. Given that guidance the past few
nights has really struggled to effectively model the dry air with
nearly the same signals, trended the RH in this forecast for
Thursday to near minimums. Thankfully winds should be light,
although and afternoon lake breeze is expected.

Friday, the ridge axis will continue over the region while a surface
low shifts into western Hudson Bay. The prevailing southerly and
southwesterly flow will advect a warmer airmass overhead, enabling
850mb temps to warm back to 10-12C. With this, expect daytime temps
to climb into the mid-upper 70s interior and mid 60s to 70F by Lake
Superior and closer to 60F by Lake Michigan. While more moisture
will advect into the area thanks to the southerly flow, mixing will
again support low RH values in the 20s for most, if not all,
interior locations.

Cold front swings through Friday evening, but as noted by the
previous shift, the trend has been and still continues to be toward
a dry passage. While some cooling is expected in the post frontal
airmass, highs in the 50s and 60s Saturday, ridging and a warm
airmass build back in Sunday. Deterministic EC, GFS, and Canadian
all suggest 850mb warming to near 12-15C by Monday, perhaps warmer.
Under mostly clear skies, widespread low to mid 80s would be
possible. Guidance suggests the heat, alongside mostly dry
conditions, could stick around for the remainder of the coming week.
Deterministic guidance suggests 925mb winds of 20+kts will accompany
this heat. If this rings true, elevated fire weather conditions will
be possible. Best chance for precip looks to be maybe mid-week.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 137 AM EDT Wed May 7 2025

VFR will be the primary flight category at IWD and CMX, while SAW
will likely deteriorate to MVFR by daybreak this morning. In the
wake of earlier cold front passage, winds have been a bit elevated
with gusts of 20 to 25 kts. This should help to mitigate any fog
threat this morning, though. Look for a return to VFR at SAW by
early afternoon and diminishing winds by this evening.

&&

.MARINE...
Issued at 305 AM EDT Wed May 7 2025

Cold front is currently exiting Lake Superior to the south and east.
20-30kts have been observed over Lake Superior in the post frontal
airmass, although the higher winds look to be sporadic based on
available observations. The potential for these elevated winds will
continue through the morning, then gradually fall below 20kts this
afternoon. Afterwards, light winds, mostly 20kts or lower looks to
hold over the lake into next week. Some potential for 20-30kt winds
exists Friday night behind another front.

&&

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

&&

$$

SHORT TERM...JTP
LONG TERM...JTP
AVIATION...TDUD
MARINE...JTP