853
FXUS63 KMQT 040640
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
240 AM EDT Thu Jul 4 2024

.KEY MESSAGES...

- Low chance (~25%) of afternoon showers/storms across interior
western Upper Michigan on Independence Day.

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

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

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 230 PM EDT Wed Jul 3 2024

RAP analysis shows mainly zonal flow setting up over the area this
afternoon as a closed low continues to move through northern
Ontario, towards Hudson Bay. Over the Great Lakes, skies have been
able to turn sunny with large-scale subsidence indicated in water
vapor imagery. However, with diurnal mixing, plenty of agitated
cumulus has popped off over the UP. This remains fairly well capped
over the west, but cooler cloud tops are apparent in the eastern UP.
This hints at a chance for some isolated to scattered showers and
storms across the central and eastern UP as we head through the late
afternoon and evening hours. Given only a few hundred j/kg of CAPE
over the area, no severe weather is expected. Though any rain totals
should be light for the most part, areas where multiple storms can
move through could see QPF in excess of a quarter inch. This is most
likely in Luce county, where the highest cloud tops are already
developing (perhaps some lake breeze convergence?).

Otherwise, temperatures are turning much warmer than yesterday, with
most of the area already well into the 70s and lower 80s. The
exception is in the eastern UP, where areas along Lake Michigan
continue to struggle to get out of the 60s courtesy of onshore flow.
Meanwhile, winds remain on the breezy side, with gusts up to 20mph
common across the western half of the UP. Higher gusts in excess of
30mph continue to be observed at times across the Keweenaw. Winds
should fall back as we head into the evening and the boundary layer
decouples.

Tonight, ridging will continue to strengthen over the forecast area,
with any lingering convection over the eastern UP wrapping up by
midnight. Outside of that, though, it will be a dry night with
overnight lows generally in the 50s, low 60s to the south.

&&

.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 /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 124 AM EDT Thu Jul 4 2024

Expect VFR conditions at the terminals through 00Z Friday.
VFR prevails for the forecast period. A low pressure system
lifting up from Wisconsin will likely bring in some showers
along with lower MVFR to possible IFR conditions to IWD late in
the period (03-06Z Friday). Showers and MVFR conditions could
also reach into CMX and SAW as well toward the end of the period
but timing is more uncertain.

&&

.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.

&&

$$

SHORT TERM...LC
LONG TERM...TAP
AVIATION...Voss
MARINE...TAP