026
FXUS63 KMQT 041726
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
126 PM EDT Thu Jul 4 2024

.KEY MESSAGES...

- Low chance (15-30%) of showers/storms this afternoon roughly from
Ironwood eastward to Manistique.

- Widespread moderate rain expected late tonight into Friday
evening. Some thunder possible.

- While not a washout...scattered shower and thunderstorm chances
return for Sunday.

&&

.UPDATE...
Issued at 944 AM EDT Thu Jul 4 2024

The forecast remains on track this morning, with a pleasant start to
the holiday area-wide. Temperatures hover in the 60s so far, but
should be able to peak well in the 70s for most. Otherwise, though
we`re staying dry so far with just some high cirrus spilling in from
a system moving over the Lower Midwest, we continue to anticipate
some weak convection across the eastern UP later today along the
lake breeze.

&&

.SHORT TERM /THROUGH THIS AFTERNOON/...
Issued at 324 AM EDT Thu Jul 4 2024

Water vapor imagery and RAP analysis show troffing from n central
Canada to se Canada. In a separate branch of flow, a shortwave trof
is emerging over the western Dakotas. This shortwave trof will
affect Upper MI weather tonight/Fri. Closer to home, after the sct
shra/tsra of yesterday aftn/evening, it`s been a quiet overnight
period. Winds are light to calm, and only some patches of mid-
level cloudiness are noted, mainly across the e. Temps have
fallen to the low/mid 50s F at the traditional cooler spots
interior w, but in general, temps range thru the upper 50s and
60s F.

Expect a nice start to Independence Day as weak sfc high pres ridge
drifts e to the western Great Lakes. This will lead to an aftn with
meso highs over Lake Superior and northern Lake MI. So, lake breezes
will rule the aftn, providing some cooling near the Lakes. Expect
high temps to range from mostly upper 60s/lwr 70s along the Lakes,
depending on how quickly lake breezes develop, to the upper 70s/lwr
80s F inland. Model consensus is for up to a few hundred j/kg of
MLCAPE to build this aftn in the interior. Lake breeze convergence
zone over the eastern fcst area should be one area that may support
some aftn convective development. With light nw gradient flow in the
morning giving the Lake Superior lake breeze an earlier start than
the Lake MI lake breeze, the convergence zone will set up closer to
Lake MI. Expect any isold shra/tsra that might develop to be across
Delta/southern Schoolcraft counties. To the w, forcing from the
aforementioned wave heading out over the Dakotas may provide some
support for isold to sct late day shra/tsra, mainly in the counties
bordering WI.

&&

.LONG TERM /TONIGHT THROUGH WEDNESDAY/...
Issued at 239 AM EDT Thu Jul 4 2024

An active weather period continues through the extended period as
the cycle of shortwaves followed by high pressure ridging continues
until around the middle to end of next week. More details follow
below.

Expect some showers and thunderstorms to make there way into the
U.P. tonight as a shortwave low over the Northern Plains is phased
with a low lifting from the Southern Plains. While the chances for
rain look best along the Wisconsin border by the time fireworks
start this evening, the rain chances look to continue increasing
across the rest of the area late tonight as the low`s center moves
through central Wisconsin. While a strong storm or two could be seen
near the Wisconsin border this evening due to MUCAPEs possibly being
as high as 1000 J/kg and 0-6 km bulk shear possibly squeaking out as
much as 30 knots, no severe weather is generally expected as the
CAPE within the atmosphere looks to rapidly deplete as the sun sets.
That being said, we could see some gusty winds, locally-heavy rain,
and small hail in the strongest storms early on. Expect rain showers
and a few thunderstorms to continue across the U.P. Friday as the
low moves through northern Lake Michigan. CAMs are kind of all over
the place right now with the rain coverage Friday. However, they are
all showing that the rainfall will be on-and-off across the region
Friday. Therefore, if you`ve got a quick outdoor activity that needs
to be done Friday, you may have a few small windows of opportunity
to do it. While flooding is not looking to be a concern tonight
through Friday night, CAMs do show some heavier rain showers and
thunderstorms occurring from time to time. Therefore, we could see
some localized heavy rainfall at a few spots up to a couple of
inches. With cloud cover hanging across the area and well-below
normal temperatures aloft moving through, expect the high
temperatures tomorrow to be notably cooler than today. This will be
most noticeable in the west, where highs will struggle to get into
the low to mid 60s. Meanwhile, highs may get close to 70 over in the
east. The rain and thunderstorm chances depart the U.P. Friday night
as the low lifts away through Lake Huron into Canada.

Expect drier and more normal temperatures come Saturday as ridging
builds in from the west. However, a shortwave low from the Canadian
Prairies looks to bring additional rain showers and thunderstorms
back over the area Sunday and Sunday night. Medium range guidance
keeps this trend of shortwaves lows followed by high pressure
ridging continuing through around the first half of this week.
However, once we get to the end of the forecast period and beyond
(last half of next week), we could see ridging remain over the area
as high pressure builds over the Central CONUS.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 125 PM EDT Thu Jul 4 2024

VFR will prevail today at IWD/CMX/SAW. There a may be a shra/tsra
late aftn/early evening around IWD and potentially SAW if anything
can fire on the lake breeze, but potential of the terminal be
impacted is too low to include anything in the TAF. Shra coverage
will increase tonight across the w half of Upper MI as a low pres
system moves ene into WI. Some tsra are also possible. With the
increasing coverage of shra, conditions will deteriorate as well.
Expect IWD/SAW to fall to IFR and CMX to MVFR. IFR ceilings may
finally settle in at CMX into Friday morning. Winds will be light,
under 10kt, thru this fcst period.

&&

.MARINE...
Issued at 239 AM EDT Thu Jul 4 2024

Light winds of 20 knots or less dominate the period as high pressure
ridging gives way to low pressure shortwaves and vice versa over the
next several days. That being said, we could see some thunderstorms
over the lake during the times when shortwave lows move near/over
the Upper Great Lakes, including this evening through Friday night
and again Sunday through Sunday night. Ridging looks to become
dominant over the Upper Great Lakes by the middle to end of next
week as high pressure builds over the Central U.S.

&&

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

&&

$$

UPDATE...
SHORT TERM...Rolfson
LONG TERM...TAP
AVIATION...LC
MARINE...TAP