323
FZUS63 KMQT 172001
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
401 PM EDT Tue Jun 17 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 29.5 inch low over far northeastern Ontario will continue
departing to the northeast, reaching northern Quebec by Wednesday
morning at 29.3 inches. Meanwhile, weak ridging gradually builds
over Lake Superior in the wake of this low, rising to 29.8 inches
over the lake by Wednesday morning. By late Wednesday, a 29.6 inch
low approaches Lake Michigan from the southwest while another 29.7
inch trough approaches Lake Superior from the northwest. These two
features merge into a 29.5 inch low over Georgian Bay Wednesday
night while a 30.0 inch high moves over northern Ontario. Weak 30.0
inch ridging then remains over Lake Superior until Friday. On
Saturday, a 29.6 inch trough moves over Lake Superior.


LSZ162-180800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
401 PM EDT Tue Jun 17 2025 /301 PM CDT Tue Jun 17 2025/

.LATE THIS AFTERNOON...Southwest winds 10 to 20 knots. Waves 1 to
3 feet.
.TONIGHT...Southwest winds 10 to 20 knots becoming west 5 to
15 knots after midnight. Waves subsiding to calm to 2 feet.
.WEDNESDAY...West winds 5 to 15 knots backing south late. Patchy
dense fog through early afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...South winds 5 to 15 knots veering west after
midnight. A slight chance of showers after midnight. Waves calm
to 2 feet.
.THURSDAY...Northeast winds 5 to 15 knots becoming east 10 to
20 knots by mid afternoon. A chance of showers through early
afternoon, then showers likely and a slight chance of
thunderstorms by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Northeast winds 5 to 15 knots. Showers likely
through midnight. A chance of thunderstorms. A chance of showers
after midnight. Waves calm to 2 feet.
.FRIDAY...East winds 10 to 20 knots backing northeast by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.FRIDAY NIGHT...Northeast winds 10 to 20 knots. Showers and a
chance of thunderstorms. Waves calm to 2 feet.
.SATURDAY...Northeast winds 10 to 20 knots. A chance of showers.
Waves calm to 2 feet.
.SUNDAY...East winds 10 to 20 knots becoming southwest 15 to
25 knots. A chance of showers and thunderstorms. Waves building
to 1 to 3 feet, then subsiding to calm to 2 feet.

$$

LSZ263-180800-
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-
401 PM EDT Tue Jun 17 2025

.LATE THIS AFTERNOON...Southwest winds 10 to 20 knots. Waves 1 to
3 feet.
.TONIGHT...Southwest winds 10 to 20 knots becoming west 5 to
15 knots after midnight, then diminishing to less than 10 knots
late. Waves subsiding to calm to 2 feet.
.WEDNESDAY...West winds less than 10 knots becoming south 5 to
15 knots in the afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...South winds 5 to 15 knots becoming west less
than 10 knots after midnight, then becoming north 5 to 15 knots
late. A slight chance of showers after midnight. Waves calm to
2 feet.
.THURSDAY...Northeast winds 5 to 15 knots veering east by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.THURSDAY NIGHT...East winds 5 to 15 knots. Showers likely
through midnight. A chance of thunderstorms. A chance of showers
after midnight. Waves calm to 2 feet.
.FRIDAY...East winds 5 to 15 knots. A chance of showers. Waves
calm to 2 feet.
.FRIDAY NIGHT...East winds 5 to 15 knots. Showers and a chance of
thunderstorms. Waves calm to 2 feet.
.SATURDAY...East winds 5 to 15 knots. A chance of showers. Waves
calm to 2 feet.
.SUNDAY...South winds 10 to 20 knots veering southwest. A chance
of showers and thunderstorms. Waves building to 2 to 4 feet.

$$

LSZ264-180800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
401 PM EDT Tue Jun 17 2025

.LATE THIS AFTERNOON...Southwest winds 10 to 20 knots. Waves 2 to
4 feet subsiding to 1 to 3 feet.
.TONIGHT...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots after midnight, then veering west late. Waves subsiding
to calm to 2 feet.
.WEDNESDAY...West winds less than 10 knots backing south in the
afternoon. Patchy fog through early afternoon. Waves calm to
2 feet.
.WEDNESDAY NIGHT...Southeast winds less than 10 knots veering
northwest after midnight, then becoming north 5 to 15 knots late.
A slight chance of rain showers after midnight. Waves calm to
2 feet.
.THURSDAY...Northeast winds 5 to 15 knots veering east by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.THURSDAY NIGHT...East winds 5 to 15 knots. A chance of rain
showers. Waves calm to 2 feet.
.FRIDAY...Southeast winds 5 to 15 knots backing east by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 5 to 15 knots. A chance of
showers through midnight. Showers after midnight. Waves calm to
2 feet.
.SATURDAY...East winds 5 to 15 knots veering southeast. A chance
of showers. Waves calm to 2 feet.
.SUNDAY...Southeast winds 5 to 15 knots becoming southwest 10 to
20 knots. A chance of showers. Waves building to 2 to 4 feet.

$$

LSZ265-180800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
401 PM EDT Tue Jun 17 2025

.LATE THIS AFTERNOON...West winds 10 to 20 knots. Waves calm to
2 feet.
.TONIGHT...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots after midnight. Waves calm to 2 feet.
.WEDNESDAY...West winds 5 to 15 knots backing east in the
afternoon. A slight chance of showers by mid afternoon. Waves
calm to 2 feet.
.WEDNESDAY NIGHT...East winds 5 to 15 knots veering west after
midnight, then veering northwest late. A slight chance of showers
through midnight. Waves calm to 2 feet.
.THURSDAY...North winds 10 to 20 knots veering northeast by mid
afternoon. A chance of showers by mid afternoon. Waves calm to
2 feet.
.THURSDAY NIGHT...Southeast winds 5 to 15 knots. A chance of
thunderstorms through midnight. A chance of showers. Waves calm
to 2 feet.
.FRIDAY...Southeast winds 10 to 20 knots backing east by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 10 to 20 knots. Showers and a
chance of thunderstorms. Waves calm to 2 feet.
.SATURDAY...East winds 10 to 20 knots veering southeast. A chance
of showers and thunderstorms. Waves calm to 2 feet.
.SUNDAY...South winds 15 to 25 knots veering southwest. A chance
of showers. Waves calm to 2 feet.

$$

LSZ266-180800-
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-
401 PM EDT Tue Jun 17 2025

.LATE THIS AFTERNOON...West winds 10 to 20 knots. Waves 3 to
5 feet occasionally to 7 feet subsiding to 2 to 4 feet.
.TONIGHT...South winds 5 to 15 knots veering southwest late.
Patchy fog after midnight. Waves subsiding to calm to 2 feet.
.WEDNESDAY...Southwest winds 5 to 15 knots backing northeast in
the afternoon, then veering east late. A chance of showers.
Patchy fog by mid afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...Northeast winds 5 to 15 knots backing
northwest after midnight. A slight chance of rain showers. Waves
calm to 2 feet.
.THURSDAY...North winds 10 to 20 knots diminishing to 5 to
15 knots by mid afternoon. A chance of showers by mid afternoon.
Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 5 to 15 knots increasing to
10 to 20 knots after midnight. A chance of showers. Waves calm to
2 feet.
.FRIDAY...Southeast winds 10 to 20 knots. A chance of showers.
Waves calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 10 to 20 knots. A chance of
showers through midnight. A chance of thunderstorms. Showers
after midnight. Waves building to 1 to 3 feet.
.SATURDAY...Southeast 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.
.SUNDAY...South winds 15 to 25 knots. A chance of showers. Waves
building to 3 to 5 feet occasionally to 7 feet, then subsiding to
2 to 4 feet.

$$

LSZ267-180800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
401 PM EDT Tue Jun 17 2025

.LATE THIS AFTERNOON...West winds 10 to 20 knots. Patchy fog.
Waves 3 to 5 feet occasionally to 7 feet subsiding to 2 to
4 feet.
.TONIGHT...South winds 5 to 15 knots. Patchy fog. Waves subsiding
to calm to 2 feet.
.WEDNESDAY...South winds 5 to 15 knots backing east in the
afternoon, then backing northeast late. A chance of showers.
Patchy dense fog by mid afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...Northeast winds 5 to 15 knots backing north
after midnight, then becoming northwest 10 to 20 knots late. A
chance of rain showers. Waves calm to 2 feet.
.THURSDAY...North winds 10 to 20 knots backing northwest by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.THURSDAY NIGHT...Northwest winds 5 to 15 knots becoming south
10 to 20 knots after midnight. A chance of showers. Waves calm to
2 feet.
.FRIDAY...South winds 10 to 20 knots backing southeast by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 10 to 20 knots. A chance of
showers through midnight. Showers after midnight. Waves calm to
2 feet.
.SATURDAY...Southeast winds 10 to 20 knots. Showers likely. A
chance of thunderstorms. A chance of showers. Waves building to
1 to 3 feet.
.SUNDAY...South winds 15 to 25 knots. A chance of showers. Waves
building to 2 to 4 feet.

$$

LSZ261-180200-
MAFOR 1721/
Superior West 12520 11610 13600 12500. Waves 1 to 3 feet tonight.
Waves 1 foot or less Wednesday.

Superior North Central 13520 11510 13600 11400. Waves 2 to 4 feet
tonight. Waves 1 to 2 feet Wednesday.

Superior South Central 11610 11510 11410 12500 11600 11800 11200.
Waves 1 to 3 feet subsiding to 1 foot or less tonight. Waves 1
foot or less Wednesday.

Superior East 11620 11500 14400 11300 11200. Waves 3 to 5 feet
subsiding to 1 to 2 feet tonight. Waves 1 foot or less Wednesday.

$$

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