077
FZUS63 KMQT 090202
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1001 PM EDT Fri Aug 8 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...

High pressure at 30.3 inches remains centered off the New England
coast through today 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 ridging at around 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, sending a 29.9 inch trough over Lake Superior
Monday with a secondary trough around 29.9 inches rotating through
the lake Tuesday into Wednesday.


LSZ162-090800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1001 PM EDT Fri Aug 8 2025 /901 PM CDT Fri Aug 8 2025/

.REST OF TONIGHT...Southeast winds 10 to 20 knots veering south
after midnight. A chance of showers and thunderstorms. Waves calm
to 2 feet building to 1 to 3 feet.
.SATURDAY...South winds 10 to 20 knots veering southwest in the
afternoon. A chance of showers and thunderstorms. Waves subsiding
to calm to 2 feet.
.SATURDAY NIGHT...Southwest winds 10 to 20 knots. A slight chance
of showers through midnight. Waves calm to 2 feet.
.SUNDAY...Southwest winds 15 to 25 knots. Waves building to 2 to
4 feet, then subsiding to 1 to 3 feet.
.SUNDAY NIGHT...West winds 10 to 20 knots. Waves subsiding to
calm to 2 feet.
.MONDAY...Southwest winds 10 to 20 knots. Waves calm to 2 feet.
.MONDAY NIGHT...Southwest winds 10 to 20 knots. Waves calm to
2 feet.
.TUESDAY...West winds 10 to 20 knots becoming north 5 to
15 knots. Waves calm to 2 feet.
.WEDNESDAY...Southeast winds 5 to 15 knots becoming east 10 to
20 knots. Waves calm to 2 feet.

$$

LSZ263-090800-
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-
1001 PM EDT Fri Aug 8 2025

.REST OF TONIGHT...South winds 5 to 15 knots increasing to 10 to
20 knots late. A chance of showers and thunderstorms. Waves calm
to 2 feet building to 2 to 4 feet.
.SATURDAY...South winds 10 to 20 knots becoming southwest 5 to
15 knots in the afternoon, then increasing to 10 to 20 knots
late. A chance of showers and thunderstorms. Waves subsiding to
calm to 2 feet, then building to 1 to 3 feet.
.SATURDAY NIGHT...Southwest winds 10 to 20 knots diminishing to
5 to 15 knots late. A slight chance of showers. Waves 1 to
3 feet.
.SUNDAY...Southwest winds 15 to 25 knots. Waves building to 2 to
4 feet.
.SUNDAY NIGHT...Southwest winds 10 to 20 knots becoming west 5 to
15 knots after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY NIGHT...Southwest winds 5 to 15 knots. Waves calm to
2 feet.
.TUESDAY...West winds 5 to 15 knots veering northwest. Waves calm
to 2 feet.
.WEDNESDAY...South winds 5 to 15 knots. Waves calm to 2 feet.

$$

LSZ264-090800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1001 PM EDT Fri Aug 8 2025

.REST OF TONIGHT...South winds 10 to 20 knots diminishing to 5 to
15 knots late. A chance of showers and thunderstorms. Waves 1 to
3 feet building to 2 to 4 feet.
.SATURDAY...South winds 5 to 15 knots veering southwest late. A
chance of showers and thunderstorms. Waves subsiding to 1 to
3 feet.
.SATURDAY NIGHT...South winds 5 to 15 knots veering southwest
after midnight. A chance of showers. Waves 1 to 3 feet.
.SUNDAY...Southwest winds 10 to 20 knots. Waves 1 to 3 feet.
.SUNDAY NIGHT...Southwest winds 5 to 15 knots veering west after
midnight. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY NIGHT...South winds 5 to 15 knots veering southwest after
midnight. Waves calm to 2 feet.
.TUESDAY...Southwest winds 5 to 15 knots veering northwest. Waves
calm to 2 feet.
.WEDNESDAY...South winds 5 to 15 knots. Waves calm to 2 feet.

$$

LSZ265-090800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1001 PM EDT Fri Aug 8 2025

.REST OF TONIGHT...South winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. A slight chance of showers and
thunderstorms. Waves 1 to 3 feet.
.SATURDAY...South winds 10 to 20 knots. A chance of showers and
thunderstorms. Waves subsiding to calm to 2 feet, then building
to 1 to 3 feet.
.SATURDAY NIGHT...South winds 10 to 20 knots veering southwest
after midnight. A slight chance of thunderstorms through
midnight. A chance of showers. Waves calm to 2 feet.
.SUNDAY...South winds 10 to 20 knots. A slight chance of showers.
Waves calm to 2 feet.
.SUNDAY NIGHT...Southwest winds 10 to 20 knots diminishing to
5 to 15 knots after midnight. A slight chance of showers after
midnight. Waves calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...South winds 5 to 15 knots becoming southwest
10 to 20 knots after midnight. Waves calm to 2 feet.
.TUESDAY...Southwest winds 10 to 20 knots becoming west 5 to
15 knots. Waves calm to 2 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots becoming southwest
5 to 15 knots. Waves calm to 2 feet.

$$

LSZ266-090800-
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-
1001 PM EDT Fri Aug 8 2025

.REST OF TONIGHT...South winds 15 to 25 knots. A slight chance of
showers and thunderstorms after midnight. Waves 2 to 4 feet.
.SATURDAY...South winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon. A chance of showers and thunderstorms.
Waves subsiding to 1 to 3 feet.
.SATURDAY NIGHT...South winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. Showers likely and a slight chance of
thunderstorms through midnight, then a chance of showers after
midnight. Waves 1 to 3 feet.
.SUNDAY...South winds 10 to 20 knots. A chance of showers. Waves
subsiding to calm to 2 feet.
.SUNDAY NIGHT...South winds 10 to 20 knots becoming southwest
5 to 15 knots after midnight. A slight chance of showers. Waves
calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY NIGHT...South winds 5 to 15 knots. Waves calm to 2 feet.
.TUESDAY...Southwest winds 10 to 20 knots becoming northwest 5 to
15 knots. Waves calm to 2 feet.
.WEDNESDAY...North winds 10 to 20 knots becoming southwest 5 to
15 knots. Waves calm to 2 feet.

$$

LSZ267-090800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1001 PM EDT Fri Aug 8 2025

.REST OF TONIGHT...South winds 15 to 25 knots. A slight chance of
showers. A slight chance of thunderstorms after midnight. Waves
1 to 3 feet.
.SATURDAY...South winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then veering southwest late. A slight
chance of showers and thunderstorms. Waves building to 2 to
4 feet, then subsiding to calm to 2 feet.
.SATURDAY NIGHT...South winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. Showers likely and a chance of
thunderstorms. Waves building to 1 to 3 feet.
.SUNDAY...South winds 10 to 20 knots. A chance of showers and a
slight chance of thunderstorms. Waves subsiding to calm to
2 feet.
.SUNDAY NIGHT...South winds 10 to 20 knots. A chance of showers
and a slight chance of thunderstorms. Waves calm to 2 feet.
.MONDAY...Southwest winds 10 to 20 knots backing south by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.MONDAY NIGHT...South winds 10 to 20 knots. A chance of showers.
Waves calm to 2 feet.
.TUESDAY...South winds 10 to 20 knots veering west. A chance of
showers. Waves calm to 2 feet.
.WEDNESDAY...Northwest winds 10 to 20 knots backing southwest.
Waves calm to 2 feet.

$$

LSZ261-090800-
MAFOR 0903/
Superior West 12420 11520 11420 12520 11510 11520. A chance of
showers and thunderstorms overnight and Saturday. Waves 1 to 3
feet.

Superior North Central 14420 12410 11510 11410. A chance of
showers and thunderstorms overnight and Saturday. A chance of
showers Saturday evening. Waves 1 to 3 feet building to 2 to 4
feet overnight. Waves 2 to 4 feet subsiding to 1 to 3 feet
Saturday. Waves 1 to 3 feet Saturday evening.

Superior South Central 15420 12410. A chance of showers Saturday
morning, then a chance of showers and thunderstorms Saturday
afternoon. A chance of showers and thunderstorms Saturday
evening. Waves 1 to 3 feet overnight and Saturday. Waves 2 feet
or less Saturday evening.

Superior East 13420 11430 11420 11410 11420 11426. Waves 2 to 4
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