305
FZUS63 KMQT 081401
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1001 AM EDT Tue Jul 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...

A weak 30.0 to 30.1 inch ridge stays in place over Lake Superior
through much of this week. That being said, a weak 29.9 inch low
over western Lake Superior this morning tracks to the remainder of
the Upper Great Lakes the rest of today through tonight. Ridging is
pushed east by a 29.7 inch phasing low over the Northern Plains on
Friday, with the low deepening to 29.5 inches over northern Ontario
by Saturday as 29.7 inch troughing moves over Lake Superior. Weak
ridging of at least 29.8 inches then returns to Lake Superior Sunday
morning.


LSZ162-082000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1001 AM EDT Tue Jul 8 2025 /901 AM CDT Tue Jul 8 2025/

.REST OF TODAY...Northeast winds 5 to 15 knots. Waves calm to
2 feet.
.TONIGHT...Northeast winds 5 to 15 knots backing northwest late.
Waves calm to 2 feet.
.WEDNESDAY...Northwest winds 5 to 15 knots backing southwest in
the afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...East winds 5 to 15 knots. Waves calm to
2 feet.
.THURSDAY...East winds 5 to 15 knots. Waves calm to 2 feet.
.THURSDAY NIGHT...Northeast winds 5 to 15 knots. A chance of
showers after midnight. Waves calm to 2 feet.
.FRIDAY...East winds 5 to 15 knots becoming northeast 10 to
20 knots. Showers likely and a chance of thunderstorms. Waves
calm to 2 feet.
.SATURDAY...West winds 10 to 20 knots. A chance of showers. Waves
calm to 2 feet.

$$

LSZ263-082000-
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 AM EDT Tue Jul 8 2025

.REST OF TODAY...East winds 5 to 15 knots backing northeast in
the afternoon. A slight chance of showers and thunderstorms by
late morning. Waves calm to 2 feet.
.TONIGHT...Northeast winds 5 to 15 knots becoming north less than
10 knots after midnight. Waves calm to 2 feet.
.WEDNESDAY...North winds less than 10 knots becoming northwest
5 to 15 knots in the afternoon, then backing west late. Waves
calm to 2 feet.
.WEDNESDAY NIGHT...West winds less than 10 knots backing east
after midnight. Waves calm to 2 feet.
.THURSDAY...East winds 5 to 15 knots. Waves calm to 2 feet.
.THURSDAY NIGHT...East winds 5 to 15 knots veering south after
midnight. Waves calm to 2 feet.
.FRIDAY...East winds 5 to 15 knots. A chance of showers. A chance
of thunderstorms. Showers likely. Waves calm to 2 feet.
.SATURDAY...West winds 5 to 15 knots. A chance of showers. Waves
calm to 2 feet.

$$

LSZ264-082000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1001 AM EDT Tue Jul 8 2025

.REST OF TODAY...East winds 5 to 15 knots backing northeast late.
A chance of showers and thunderstorms. Waves calm to 2 feet.
.TONIGHT...Northeast winds less than 10 knots backing north after
midnight. A slight chance of showers through midnight. Waves calm
to 2 feet.
.WEDNESDAY...North winds 5 to 15 knots backing west late. Waves
calm to 2 feet.
.WEDNESDAY NIGHT...West winds less than 10 knots. Waves calm to
2 feet.
.THURSDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 5 to 15 knots. Waves calm to
2 feet.
.FRIDAY...Southeast winds 5 to 15 knots. A chance of showers.
Waves calm to 2 feet.
.SATURDAY...Southeast winds 5 to 15 knots veering west. A chance
of showers. Waves calm to 2 feet.

$$

LSZ265-082000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1001 AM EDT Tue Jul 8 2025

.REST OF TODAY...Southeast winds 10 to 20 knots diminishing to
5 to 15 knots in the afternoon, then backing northeast late. A
chance of showers and thunderstorms. Waves calm to 2 feet.
.TONIGHT...Northeast winds 5 to 15 knots backing northwest late.
Waves calm to 2 feet.
.WEDNESDAY...Northwest winds 5 to 15 knots increasing to 10 to
20 knots in the afternoon, then diminishing to 5 to 15 knots
late. Waves calm to 2 feet.
.WEDNESDAY NIGHT...Northwest winds 5 to 15 knots diminishing to
less than 10 knots after midnight. Waves calm to 2 feet.
.THURSDAY...East 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. Waves calm to 2 feet.
.FRIDAY...Southeast winds 10 to 20 knots. A chance of showers.
Waves calm to 2 feet.
.SATURDAY...Southeast winds 10 to 20 knots veering west. A chance
of showers. Waves calm to 2 feet.

$$

LSZ266-082000-
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 AM EDT Tue Jul 8 2025

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

$$

LSZ267-082000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1001 AM EDT Tue Jul 8 2025

.REST OF TODAY...East winds 5 to 15 knots. A slight chance of
showers. A slight chance of thunderstorms by mid afternoon. Waves
calm to 2 feet.
.TONIGHT...East winds 5 to 15 knots backing north late. A slight
chance of showers through midnight. Waves calm to 2 feet.
.WEDNESDAY...North winds 5 to 15 knots becoming northwest 10 to
20 knots in the afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...Northwest winds 5 to 15 knots. Waves calm to
2 feet.
.THURSDAY...Northwest winds 5 to 15 knots. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 5 to 15 knots. Waves calm to
2 feet.
.FRIDAY...Southeast winds 10 to 20 knots. A chance of showers.
Waves calm to 2 feet.
.SATURDAY...Southeast winds 10 to 20 knots veering southwest. A
chance of showers. Waves building to 1 to 3 feet, then subsiding
to calm to 2 feet.

$$

LSZ261-082000-
MAFOR 0815/
Superior West 13110 12100 11800 12700. Waves 1 to 2 feet.

Superior North Central 11310 11200 12100 14800. A chance of
showers and thunderstorms this afternoon. Waves 1 to 2 feet.

Superior South Central 11320 11310 11110 11100 11800 13700. A
chance of showers and thunderstorms this afternoon and evening.
Waves 2 feet or less.

Superior East 11310 11200 11210 12200 11100 12800. A chance of
showers this evening. Waves 1 foot or less.

$$

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