562
FXUS63 KMQT 201147
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
747 AM EDT Thu Jun 20 2024

.KEY MESSAGES...

-Better rain chances return tonight along with thunderstorms by
 Friday.

-Keeping an eye on flooding concerns near Harvey along the Chocolay
River and over the west due to the high recent rainfall amounts.

- Moderate to heavy rain likely through first half of
weekend.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 432 AM EDT Thu Jun 20 2024

Current water vapor imagery/surface analysis early this morning show
a stationary frontal boundary draped across much of the Lower
Midwest and eastern Great Lakes Region. Any showers and isolated
rumbles of thunder associated with it overnight have now moved east
of Upper Michigan with just a few lingering rain showers over the
far south and east. Per time cross sections, will trend toward a dry
forecast through much of the morning with a slight uptick in rain
chances from the west across the southern half of the forecast area.
 Better rain chances will not arrive until tonight, though, as WAA
overspreads the area ahead of the next approaching short wave.
Meanwhile, expect temperatures at to slightly below normal today and
tonight with highs generally topping off in the low to mid 70s (60s
across Keweenaw) and lows in the upper 40s to mid 50s.

We continue to keep an eye on flooding concerns along the Chocolay
River near Harvey and also over the west where some places got
rainfall in excess of 3 inches (some as much as 5 inches!).

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 347 AM EDT Thu Jun 20 2024

After a brief quiet period for Thursday, active weather returns to
finish out the week. A warm front will be lifting through the Upper
MIssissippi Valley into Friday as another shortwave ejects out of
the Rockies. Warm advection precipitation should move into the
western UP by mid-morning while the front stalls out somewhere
across central or northern WI. Showers continue on and off throughout
the day, most likely over the southwest and south-central UP, closer
in proximity to the boundary. With a pretty decent cap developing in
soundings, strong convection is not expected, but a few rumbles of
thunder will not be ruled out. As the main upper trough moves out of
the Plains later Friday, a surface low will deepen and lift
northeastward along the boundary toward Upper Michigan by early
Saturday. The moisture increase will be significant Friday night
into Saturday with PWATs approaching 2 inches, so Saturday will
likely be a washout for most with moderate to heavy rain. However,
will note a trend among some of the guidance to keep the boundary
(and heaviest rainfall) more to our south, across northern or
central WI. Still, by the time this first round of rain winds down
Saturday evening, much of the area will likely have picked up
rainfall totals in excess of an inch (70-90% chance among ensemble
guidance) with the Euro coming in even higher. Given recent heavy
rains across portions of the U.P. this week ponding of water will
and increase in stream flows will be the primary threats.

As the low continues to move ENE through the area Saturday night,
the cold front will push any remaining precipitation east of the
area. While some drying will occur on Sunday, one more shortwave
dropping down from the Canadian border could produce enough lift for
a few additional showers on Sunday. However, will note that
soundings are rather moisture-starved, so showers should be light.

Moving into early next week, expect ridging and and warming as high
pressure moves from the Plains through the Midwest. Then, a series
of quickly-moving shortwaves and associated cold frontal passage
will bring in additional chances for showers and storms Tuesday
through the middle of next week, but timing differences persist
among various model guidance this far out.

With clouds and rain through the first half of the weekend,
temperatures will be a little below normal before climbing back
above normal early next week.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 747 AM EDT Thu Jun 20 2024

VFR conditions will prevail for the duration of the TAF period with
light winds.  A few rain showers that could filter into IWD and SAW
later today/tonight, but no impacts are expected.

&&

.MARINE...
Issued at 347 AM EDT Thu Jun 20 2024

Winds will be turning mainly over to the N to NE today, with a
stretch of light winds expected today into early Saturday with
surface ridging over Lake Superior. A surface low lifting through
the Upper Lakes on Saturday will lead to northeasterly winds up to
20-25 knots over the western Lake during the day. Northwesterly
winds behind the departing low should stay around or just below 20
knots on Sunday. Southwesterly winds will return early next week
increasing to 20-25 knots ahead of another weak cold front by
Tuesday afternoon.

Moderate to heavy rain will be possible across the south half of the
Lake from later Friday through Saturday which could lead to some
dense fog development during that time.

&&

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

&&

$$

SHORT TERM...TDUD
LONG TERM...LC
AVIATION...TDUD
MARINE...LC