699
FZUS63 KMQT 061402
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1002 AM EDT Wed Aug 6 2025

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...

Expansive high pressure averaging 30.3 inches encompasses much of
eastern Canada and the Great Lakes through today. This high shifts
to New England this afternoon and remains into Thursday while low
pressure averaging 29.6 inches emerges off the Rockies into the
Northern Plains. The low strengthens to 29.5 inches as it lifts into
the Canadian Prairies over the weekend, while high pressure at 30.2
inches remains over much of the Eastern Seaboard, leaving Lake
Superior sandwiched between the two features. The high erodes away
by early next week as the low lifts into Hudson Bay.


LSZ162-062000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1002 AM EDT Wed Aug 6 2025 /902 AM CDT Wed Aug 6 2025/

.REST OF TODAY...Southeast winds 10 to 20 knots backing east in
the afternoon. Haze. A chance of showers. A slight chance of
thunderstorms by mid afternoon. Waves calm to 2 feet.
.TONIGHT...East winds 10 to 20 knots becoming south 5 to 15 knots
after midnight. Haze. A chance of showers and thunderstorms.
Waves calm to 2 feet.
.THURSDAY...Southwest winds 10 to 20 knots backing south in the
afternoon, then diminishing to 5 to 15 knots late. A slight
chance of showers and thunderstorms through early afternoon.
Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 5 to 15 knots. Waves calm to
2 feet.
.FRIDAY...Southeast winds 5 to 15 knots backing east by mid
afternoon. A slight chance of showers and thunderstorms by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...East winds 10 to 20 knots veering south after
midnight. A chance of showers and thunderstorms. Waves calm to
2 feet.
.SATURDAY...Southwest winds 10 to 20 knots. A chance of
thunderstorms. A chance of showers. Waves building to 1 to
3 feet, then subsiding to calm to 2 feet.
.SUNDAY...Southwest winds 10 to 20 knots veering west. Waves
building to 1 to 3 feet, then subsiding to calm to 2 feet.

$$

LSZ263-062000-
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-
1002 AM EDT Wed Aug 6 2025

.REST OF TODAY...Southeast winds 5 to 15 knots backing east in
the afternoon. Haze. A slight chance of showers. Waves calm to
2 feet.
.TONIGHT...Southeast winds 10 to 20 knots veering south after
midnight, then diminishing to 5 to 15 knots late. Haze. A chance
of thunderstorms and showers. Waves building to 1 to 3 feet, then
subsiding to calm to 2 feet.
.THURSDAY...Southwest winds 5 to 15 knots backing south late. A
slight chance of showers and thunderstorms. Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 5 to 15 knots veering southwest
after midnight. A slight chance of showers and thunderstorms
through midnight. Waves calm to 2 feet.
.FRIDAY...South winds 5 to 15 knots backing east by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 5 to 15 knots becoming south
10 to 20 knots after midnight. A chance of showers. A chance of
thunderstorms after midnight. Waves calm to 2 feet.
.SATURDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots. A chance of thunderstorms. A chance of showers. Waves
building to 1 to 3 feet, then subsiding to calm to 2 feet.
.SUNDAY...Southwest winds 10 to 20 knots. Waves subsiding to calm
to 2 feet.

$$

LSZ264-062000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1002 AM EDT Wed Aug 6 2025

.REST OF TODAY...Southeast winds 5 to 15 knots increasing to
10 to 20 knots late. Haze. Waves calm to 2 feet building to 1 to
3 feet.
.TONIGHT...Southeast winds 10 to 20 knots veering south after
midnight, then diminishing to 5 to 15 knots late. Haze. A chance
of showers and a slight chance of thunderstorms. Waves 1 to
3 feet.
.THURSDAY...South winds 5 to 15 knots. A slight chance of showers
and thunderstorms through early afternoon. Waves subsiding to
calm to 2 feet.
.THURSDAY NIGHT...South winds 5 to 15 knots veering southwest
after midnight. A slight chance of showers and thunderstorms.
Waves calm to 2 feet.
.FRIDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 5 to 15 knots veering south after
midnight. A chance of showers. A chance of thunderstorms after
midnight. Waves calm to 2 feet.
.SATURDAY...South winds 10 to 20 knots becoming southwest 5 to
15 knots. A chance of showers and thunderstorms. Waves building
to 1 to 3 feet, then subsiding to calm to 2 feet.
.SUNDAY...Southwest winds 5 to 15 knots. Waves building to 1 to
3 feet, then subsiding to calm to 2 feet.

$$

LSZ265-062000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1002 AM EDT Wed Aug 6 2025

.REST OF TODAY...Southeast winds 10 to 20 knots increasing to
15 to 25 knots late. Haze. Waves calm to 2 feet.
.TONIGHT...Southeast winds 10 to 20 knots veering south after
midnight. Haze. A chance of showers and a slight chance of
thunderstorms after midnight. Waves calm to 2 feet.
.THURSDAY...South winds 10 to 20 knots backing southeast late. A
slight chance of showers and thunderstorms. Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 10 to 20 knots. A slight chance of
showers and thunderstorms. Waves calm to 2 feet.
.FRIDAY...South winds 10 to 20 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 10 to 20 knots. A chance of showers
and thunderstorms after midnight. Waves calm to 2 feet.
.SATURDAY...South winds 15 to 25 knots becoming southwest 10 to
20 knots. A chance of showers and thunderstorms. Waves calm to
2 feet.
.SUNDAY...South winds 10 to 20 knots veering southwest. A chance
of showers. Waves calm to 2 feet.

$$

LSZ266-062000-
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-
1002 AM EDT Wed Aug 6 2025

.REST OF TODAY...Southeast winds 10 to 20 knots backing east
late. Haze. Waves calm to 2 feet.
.TONIGHT...Southeast winds 10 to 20 knots veering south after
midnight. Haze. A slight chance of showers and thunderstorms
after midnight. Waves building to 1 to 3 feet, then subsiding to
calm to 2 feet.
.THURSDAY...South winds 10 to 20 knots. A slight chance of
showers and thunderstorms. Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 10 to 20 knots. A slight chance of
showers and thunderstorms. Waves calm to 2 feet.
.FRIDAY...South winds 10 to 20 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 10 to 20 knots. Waves building to
1 to 3 feet.
.SATURDAY...South winds 15 to 25 knots diminishing to 10 to
20 knots. A chance of showers and thunderstorms. Waves 1 to
3 feet.
.SUNDAY...South winds 10 to 20 knots veering southwest. A chance
of showers. Waves subsiding to calm to 2 feet.

$$

LSZ267-062000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1002 AM EDT Wed Aug 6 2025

.REST OF TODAY...Southeast winds 10 to 20 knots backing east in
the afternoon. Haze. Waves calm to 2 feet.
.TONIGHT...Southeast winds 10 to 20 knots veering south late.
Haze. A slight chance of showers after midnight. Waves calm to
2 feet.
.THURSDAY...South winds 10 to 20 knots backing southeast in the
afternoon. A slight chance of showers. A slight chance of
thunderstorms by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 10 to 20 knots. A chance of showers
and thunderstorms. Waves calm to 2 feet.
.FRIDAY...South winds 10 to 20 knots backing southeast by mid
afternoon. A slight chance of showers and thunderstorms through
early afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 10 to 20 knots. Waves building to
1 to 3 feet.
.SATURDAY...South winds 15 to 25 knots diminishing to 10 to
20 knots. A chance of showers and thunderstorms. Waves 1 to
3 feet.
.SUNDAY...South winds 10 to 20 knots veering southwest. A chance
of showers. Waves subsiding to calm to 2 feet.

$$

LSZ261-062000-
MAFOR 0615/
Superior West 11310 12210 12310 11410 12510. A chance of showers
late this morning. A chance of showers this evening, then a
chance of showers and thunderstorms overnight. Waves 1 to 2 feet.

Superior North Central 14320 11320 11420 12410. A chance of
showers overnight and Thursday morning. Waves 1 to 3 feet.

Superior South Central 14320 14410. Waves around 1 foot.

Superior East 11300 12210 13310 12410. Waves 1 to 2 feet.

$$

WFO MQT

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

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