Great Lakes Forecast
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080
FZUS63 KMQT 170753
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
353 AM EDT Tue Sep 17 2024

For waters beyond 5 nautical miles of shore on Lake Superior.

Waves are the significant wave height - the average of the
highest 1/3 of the wave spectrum. Occasional wave height is the
average of the highest 1/10 of the wave spectrum.

.SYNOPSIS...Through Wednesday, 30.3 inch high pressure anchored
offshore of the New England Coast will extend 30.1 inch ridging back
into the Great Lakes region. During Thursday, 30.0 inch ridging will
extend from northern Quebec into the Great Lakes region. Meanwhile,
a 29.4 inch trough will emerge over the western Great Plains today.
Low pressure of 29.3 inches developing along this trough during
tonight and Wednesday will lift into southwest Manitoba Thursday
morning. As the low drifts northeast over Manitoba on Thursday, an
associated 29.6 inch trough will progress across the Dakotas. As the
low continues to track northeast to Hudson Bay during Friday, the
associated trough will weaken to 29.8 inches as it reaches western
Lake Superior. This trough will then dissipate, allowing weak 30.0
inch ridging to setup over the Upper Great Lakes on Saturday.

LSZ162-171600-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
353 AM EDT Tue Sep 17 2024 /253 AM CDT Tue Sep 17 2024/

.EARLY THIS MORNING...South winds 5 to 15 knots. Waves calm to
2 feet.
.TODAY...South winds 5 to 15 knots becoming southeast 10 to
20 knots late. Waves calm to 2 feet.
.TONIGHT...South winds 5 to 15 knots. A slight chance of showers
and thunderstorms. Waves calm to 2 feet.
.WEDNESDAY...South winds 5 to 15 knots backing east in the
afternoon, then increasing to 10 to 20 knots late. Waves calm to
2 feet.
.WEDNESDAY NIGHT...East winds 10 to 20 knots becoming southeast
5 to 15 knots after midnight. Waves calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots backing east by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. Showers likely through midnight. A chance of
thunderstorms. A chance of showers after midnight. Waves calm to
2 feet.
.FRIDAY...Southwest winds 10 to 20 knots becoming west 5 to
15 knots. Waves calm to 2 feet.
.SATURDAY...South winds 5 to 15 knots becoming northwest 10 to
20 knots late. A chance of showers. Waves calm to 2 feet.

$$

LSZ263-171600-
Lake Superior from Saxon Harbor WI to Upper Entrance to Portage
Canal MI 5NM off shore to the US/Canadian border including Isle
Royale National Park-
353 AM EDT Tue Sep 17 2024

.EARLY THIS MORNING...South winds 5 to 15 knots. Waves calm to
2 feet.
.TODAY...South winds 5 to 15 knots backing southeast late. Waves
calm to 2 feet.
.TONIGHT...South winds 5 to 15 knots. A slight chance of showers.
A slight chance of thunderstorms after midnight. Waves calm to
2 feet.
.WEDNESDAY...South winds 5 to 15 knots backing east late. A
slight chance of showers through early afternoon. Waves calm to
2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots veering south
after midnight. Waves calm to 2 feet.
.THURSDAY...Southeast winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. A chance of showers through midnight. A chance of
thunderstorms. Showers likely after midnight. Waves building to
1 to 3 feet.
.FRIDAY...South winds 5 to 15 knots veering southwest. A chance
of showers. Waves subsiding to calm to 2 feet.
.SATURDAY...Southwest winds 5 to 15 knots backing south. A chance
of showers. Waves calm to 2 feet.

$$

LSZ264-171600-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
353 AM EDT Tue Sep 17 2024

.EARLY THIS MORNING...Southwest winds 5 to 15 knots. Waves calm
to 2 feet.
.TODAY...South winds 5 to 15 knots backing southeast late. Waves
calm to 2 feet.
.TONIGHT...South winds 5 to 15 knots. Waves building to 2 to
4 feet, then subsiding to calm to 2 feet.
.WEDNESDAY...South winds 5 to 15 knots backing southeast late.
Waves calm to 2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots. Waves calm to
2 feet.
.THURSDAY...Southeast winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. Waves building to 1 to 3 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. A chance of showers. Waves 1 to 3 feet.
.FRIDAY...South winds 5 to 15 knots veering southwest. A chance
of showers. Waves subsiding to calm to 2 feet.
.SATURDAY...South winds 5 to 15 knots. A chance of showers. Waves
calm to 2 feet.

$$

LSZ265-171600-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
353 AM EDT Tue Sep 17 2024

.EARLY THIS MORNING...South winds 10 to 20 knots. Waves calm to
2 feet.
.TODAY...South winds 10 to 20 knots backing southeast late. Waves
building to 1 to 3 feet.
.TONIGHT...South winds 10 to 20 knots. Waves subsiding to calm to
2 feet.
.WEDNESDAY...South winds 5 to 15 knots becoming southeast 10 to
20 knots in the afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots veering south
after midnight. Waves calm to 2 feet.
.THURSDAY...Southeast winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. A chance of showers. Waves calm to 2 feet.
.FRIDAY...Southeast winds 10 to 20 knots becoming southwest 5 to
15 knots. A chance of showers. Waves calm to 2 feet.
.SATURDAY...East winds 5 to 15 knots becoming south 10 to
20 knots. A chance of showers. Waves calm to 2 feet.

$$

LSZ266-171600-
Lake Superior East of a line from Manitou Island to Marquette MI
and West of a line from Grand Marais MI to the US/Canadian Border
Beyond 5NM from shore-
353 AM EDT Tue Sep 17 2024

.EARLY THIS MORNING...South winds 10 to 20 knots. Waves 1 to
3 feet.
.TODAY...South winds 10 to 20 knots. Waves subsiding to calm to
2 feet, then building to 1 to 3 feet.
.TONIGHT...South winds 10 to 20 knots. Waves building to 2 to
4 feet, then subsiding to 1 to 3 feet.
.WEDNESDAY...South winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon, then backing southeast late. Waves
subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots veering south
after midnight. Waves calm to 2 feet.
.THURSDAY...Southeast winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. A chance of showers. Waves building to 1 to
3 feet.
.FRIDAY...South winds 10 to 20 knots diminishing to 5 to
15 knots. A chance of showers. Waves subsiding to calm to 2 feet.
.SATURDAY...South winds 5 to 15 knots. A chance of showers. Waves
calm to 2 feet.

$$

LSZ267-171600-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
353 AM EDT Tue Sep 17 2024

.EARLY THIS MORNING...South winds 10 to 20 knots. Waves calm to
2 feet.
.TODAY...South winds 10 to 15 knots. Waves calm to 2 feet.
.TONIGHT...South winds 10 to 15 knots. Waves calm to 2 feet.
.WEDNESDAY...South winds 5 to 15 knots becoming southeast in the
afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots. Waves calm to
2 feet.
.THURSDAY...Southeast winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots. Waves calm to
2 feet.
.FRIDAY...Southeast winds 10 to 20 knots veering south. A chance
of showers. Waves calm to 2 feet.
.SATURDAY...South winds 10 to 20 knots backing southeast. A
chance of showers. Waves calm to 2 feet.

$$

LSZ261-171600-
MAFOR 1709/
Superior West 13410 13310 12410. Waves 2 feet or less.

Superior North Central 11510 13410 11310 12410 11510. Waves 1 to
3 feet.

Superior South Central 11410 12420 11410 11320 11420 12410.
Waves 1 to 3 feet.

Superior East 12420 15410. Waves 1 to 3 feet.

$$

Rolfson

Experimental modernized open lake forecast is available online at
weather.gov/mqt/glftable

Graphical marine forecasts are available online at:
weather.gov/greatlakes