994
FXUS63 KMQT 171722
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
122 PM EDT Tue Sep 17 2024

.KEY MESSAGES...

- Extended stretch of well above normal temperatures continues
  through at least Thursday with highs mainly in the upper 70s
  and 80s.

- Next credible chances of precipitation arrive Thursday night
  and continues through Friday night. More rain is possible
  early next week.

&&

.SHORT TERM /THROUGH TODAY/...
Issued at 121 PM EDT Tue Sep 17 2024

Dry and warm airmass continued to sit over the Upper Great Lakes
today. Outside of some mid-high clouds here and there, and some
recently developing diurnal cumulus in the west, the forecast area
has been mostly clear which enabled many to easily break into the
70s before noon. In fact, many locations were beating hard on the 80
degree door at that point. As of publishing this discussion, most
surface observations were in the upper 70s to low 80s, which is
approximately 10 to 15 degrees above normal for mid-September. Under
mostly light southerly flow, daytime mixing has supported dewpoints
in the mid 50s to low 60s. This is yielding RH values mostly in 50s
and 40s in areas removed from Lake Michigan`s influence. Some drier
locations have fallen into the 30s as well. As we progress through
the remainder of the afternoon, I expect temps to climb a little
more and RH values in the 40s to be more widespread with some 30s
here and there before recovering with the waning heat. Expecting
clear skies to continue through tonight, which will yield overnight
lows in the 50s and 60s, save the interior portions of south-central
and east, which could slip into the 40s. Patchy overnight fog will
be possible as well, particularly in the interior spots of central
and eastern Upper Michigan.

&&

.LONG TERM /TONIGHT THROUGH MONDAY/...
Issued at 328 AM EDT Tue Sep 17 2024

Expect the dry and very warm weather to remain over the area early
in the extended period before a cold front moves in Thursday night
through Friday night and brings some much needed rainfall to the
Upper Peninsula. After a quick dry spell early this weekend, expect
additional rain chances early next week as a low pressure lifts from
the Southern Rockies into the Upper Midwest.

High pressure ridging persists over the U.P. tonight into Thursday
as a vertically-stacked low continues to lift from the Intermountain
West into the Canadian Prairies. The ridging will allow sunny skies
and the very warm temperatures to continue through the middle of
this week; we could still flirt with tying or breaking the max
temperature record in several spots on Wednesday and Thursday, even
though we aren`t expected to be as warm as we have been the past
couple of days. In addition, with the lack of rainfall over the
area, especially over the central and east over the last several
days, some fire weather partners may be concerned about some of the
fuels continuing to dry-out. Nevertheless, with the high pressure
ridging persisting overhead, winds are expected to remain fairly
light from the south, and min RHs are expected to remain above 30%.
While some shortwave action over northern Ontario may bring some
showers and storms to Isle Royale and maybe (10% chance or less) to
the Keweenaw Wednesday, outside of that the next couple of days will
be perfect if you need to get any outside work done; just be sure to
take your water breaks given the sun and heat.

Some rainfall looks to return to the forecast Thursday night as a
cold front looks to meander it`s way into the western U.P. late
overnight. The front continues through the rest of the U.P. Friday
and Friday night, bringing showers and some storms across the area.
While a sharp drop in temperature isn`t expected with this front,
with the additional cloud cover overhead, expect high temperatures
to drop a little closer to normal (i.e. the 70s). That being said,
we could see some record high min temperature records broken
Thursday night and possibly even Friday night over the east given
the antecedent warm air ahead of the front and the associated cloud
cover. In addition, the rainfall along the slow moving front may
bring some much-needed relief to our area, particularly because we
haven`t had much rainfall over the past week and we are already
experiencing abnormally dry conditions (D0) according to the drought
monitor. As for severe weather, none is currently expected given the
relatively modest lapse rates and wind shear.

While model guidance begins to noticeably spread this weekend and
continues increasingly so early next week, we should see a short dry
period at least early this weekend as some ridging scoots through
the Upper Great Lakes. Nevertheless, the differing model suites do
bring a stacked low pressure from the Southern Rockies up into the
Upper Midwest by early next week. This low looks to bring some much-
needed additional rainfall across the U.P. via a front or two.
However, the rain chances and timing are still dependent on the
low`s placement and timing. In addition, temperatures look to
continue decreasing early next week, with highs now projected to
only get into the 60s.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 121 PM EDT Tue Sep 17 2024

Dry airmass over the region will continue VFR conditions at
KIWD/KCMX/KSAW in this TAF period. Winds will be mostly southerly
save for the afternoon lake breeze at KCMX. There may be 15 to 20 kt
gusts at KIWD and KSAW this afternoon.

&&

.MARINE...
Issued at 328 AM EDT Tue Sep 17 2024

Light winds of generally 20 knots or less continue for the next
several days has high pressure ridging this week finally gives way
to a cold front moving through Thursday through Friday night. This
front could bring some showers and storms over Lake Superior, as
well as some stronger winds above 20 knots as it slowly crawls from
west to east. Moving into this weekend, there is some model spread
on when a low pressure lifting from the Southern Rockies will arrive
over the Upper Midwest (as well as it`s placement). However, we may
see winds increase above 20 knots again come late this weekend/early
next week as the low approaches.

Otherwise, the only other thing we might see is some showers and
storms over the northern and western lake tonight into Wednesday as
a shortwave lifts across northern Ontario.

&&

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

&&

$$

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