797
FZUS63 KMQT 032001
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
401 PM EDT Wed Sep 3 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 northeast Ontario retrogrades westward over far
northern Ontario tomorrow as it deepens to 29.3 inches. While this
low remains in place tomorrow night, a quick moving low traverses
through Wisconsin at 29.4 inches. This low then lifts northeast into
Ontario by Friday afternoon, then to near James Bay Friday night
while consolidating with the northern Ontario low. The consolidated
low then shifts northeast through far northern Quebec on Saturday as
30.1 inch high pressure moves into the Midwest for the weekend,
strengthening to 30.3 inches over the Upper Mississippi Valley on
Sunday. This high brings 30.2 inch ridging over Lake Superior Sunday
night. Ridging begins to dissipate over the Upper Great Lakes on
Monday as the high continues east towards New England.


LSZ162-040800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
401 PM EDT Wed Sep 3 2025 /301 PM CDT Wed Sep 3 2025/

.LATE THIS AFTERNOON...Northwest winds 20 to 30 knots. A slight
chance of waterspouts. A chance of showers. Waves 3 to 6 feet
occasionally to 8 feet.
.TONIGHT...Northwest winds 15 to 25 knots. A slight chance of
waterspouts. A slight chance of showers. Waves subsiding to 3 to
5 feet occasionally to 7 feet.
.THURSDAY...West winds 15 to 25 knots increasing to 20 to
30 knots in the afternoon, then diminishing to 15 to 25 knots
late. A chance of showers. Waves subsiding to 2 to 4 feet.
.THURSDAY NIGHT...West winds 15 to 25 knots becoming northwest
10 to 20 knots after midnight, then increasing to 15 to 25 knots
late. A chance of showers. Waves subsiding to 1 to 3 feet, then
building to 2 to 4 feet.
.FRIDAY...Northwest winds 20 to 30 knots backing west by mid
afternoon. A slight chance of showers. Waves building to 3 to
6 feet occasionally to 8 feet.
.FRIDAY NIGHT...West winds 15 to 25 knots veering northwest after
midnight. Waves subsiding to 2 to 4 feet.
.SATURDAY...Northwest winds 15 to 25 knots. Waves subsiding to
calm to 2 feet.
.SATURDAY NIGHT...North winds 10 to 20 knots backing northwest
after midnight. Waves calm to 2 feet.
.SUNDAY...Northwest winds 10 to 20 knots becoming southwest 5 to
15 knots. Waves calm to 2 feet.
.MONDAY...Southwest winds 10 to 20 knots backing south. A chance
of showers. Waves calm to 2 feet.

$$

LSZ263-040800-
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 Wed Sep 3 2025

.LATE THIS AFTERNOON...Northwest winds 20 to 30 knots. A slight
chance of waterspouts. A chance of showers. Waves 5 to 8 feet
occasionally to 10 feet.
.TONIGHT...Northwest winds 20 to 30 knots. A slight chance of
waterspouts. A chance of showers. Waves subsiding to 4 to 8 feet
occasionally to 10 feet.
.THURSDAY...West winds 20 to 30 knots. A slight chance of
waterspouts through early afternoon. A chance of showers. Waves
4 to 7 feet occasionally to 9 feet.
.THURSDAY NIGHT...West winds 15 to 25 knots diminishing to 10 to
20 knots after midnight, then becoming northwest 15 to 25 knots
late. A chance of showers. Waves subsiding to 2 to 4 feet.
.FRIDAY...Northwest winds 20 to 30 knots becoming west gales to
35 knots by mid afternoon. A slight chance of showers. Waves
building to 5 to 8 feet occasionally to 10 feet.
.FRIDAY NIGHT...Northwest winds 20 to 30 knots diminishing to
15 to 25 knots after midnight. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.SATURDAY...Northwest winds 15 to 25 knots. Waves subsiding to
2 to 4 feet.
.SATURDAY NIGHT...North winds 10 to 20 knots. Waves subsiding to
1 to 3 feet.
.SUNDAY...Northwest winds 10 to 20 knots becoming southwest 5 to
15 knots. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 10 to 20 knots backing south. Waves
building to 1 to 3 feet.

$$

LSZ264-040800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
401 PM EDT Wed Sep 3 2025

...GALE WARNING IN EFFECT UNTIL 8 PM EDT THIS EVENING...

.LATE THIS AFTERNOON...Northwest gales to 35 knots. A slight
chance of waterspouts. Showers likely. Waves 7 to 11 feet
occasionally to 13 feet.
.TONIGHT...Northwest winds 20 to 30 knots. A slight chance of
waterspouts. Showers likely through midnight. A chance of showers
after midnight. Waves subsiding to 6 to 9 feet occasionally to
11 feet.
.THURSDAY...Northwest winds 20 to 30 knots backing west in the
afternoon. A slight chance of waterspouts through early
afternoon. A chance of showers. Waves subsiding to 4 to 7 feet
occasionally to 9 feet.
.THURSDAY NIGHT...West winds 15 to 25 knots diminishing to 10 to
20 knots after midnight, then veering northwest late. A chance of
showers. Waves subsiding to 2 to 4 feet.
.FRIDAY...Northwest winds 20 to 30 knots becoming west gales to
35 knots by mid afternoon. A slight chance of showers. Waves
building to 5 to 8 feet occasionally to 10 feet.
.FRIDAY NIGHT...Northwest winds 20 to 30 knots diminishing to
15 to 25 knots after midnight. Waves subsiding to 3 to 6 feet
occasionally to 8 feet.
.SATURDAY...Northwest winds 15 to 25 knots. Waves subsiding to
2 to 4 feet.
.SATURDAY NIGHT...North winds 10 to 20 knots backing northwest
after midnight. Waves subsiding to 1 to 3 feet.
.SUNDAY...Northwest winds 10 to 20 knots becoming southwest 5 to
15 knots. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing south. Waves calm
to 2 feet.

$$

LSZ265-040800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
401 PM EDT Wed Sep 3 2025

.LATE THIS AFTERNOON...Northwest winds to 30 knots with a few
gale force gusts to 35 knots possible. A slight chance of
waterspouts. Showers likely. Waves 7 to 10 feet occasionally to
13 feet.
.TONIGHT...Northwest winds to 30 knots with a few gale force
gusts to 35 knots possible. A slight chance of waterspouts.
Showers likely through midnight. A chance of showers after
midnight. Waves subsiding to 4 to 7 feet occasionally to 9 feet.
.THURSDAY...West winds to 30 knots with a few gale force gusts to
35 knots possible diminishing to 20 to 30 knots late. A slight
chance of waterspouts through early afternoon. A chance of
showers. Waves subsiding to 3 to 5 feet occasionally to 7 feet.
.THURSDAY NIGHT...Southwest winds 15 to 25 knots diminishing to
10 to 20 knots after midnight, then becoming west 15 to 25 knots
late. A chance of showers. Waves subsiding to calm to 2 feet.
.FRIDAY...Northwest winds 20 to 30 knots backing west by mid
afternoon. A chance of showers. Waves building to 3 to 6 feet
occasionally to 8 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots diminishing to 15 to
25 knots after midnight. A chance of showers. Waves subsiding to
2 to 4 feet.
.SATURDAY...Northwest winds 15 to 25 knots. Waves subsiding to
calm to 2 feet.
.SATURDAY NIGHT...Northwest winds 10 to 20 knots. Waves calm to
2 feet.
.SUNDAY...Northwest winds 10 to 20 knots backing southwest. Waves
calm to 2 feet.
.MONDAY...Southwest winds 10 to 20 knots backing south. Waves
calm to 2 feet.

$$

LSZ266-040800-
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 Wed Sep 3 2025

.LATE THIS AFTERNOON...Northwest winds to 30 knots with a few
gale force gusts to 40 knots possible. A slight chance of
waterspouts. Showers likely. Waves 8 to 11 feet occasionally to
14 feet building to 9 to 12 feet occasionally to 15 feet.
.TONIGHT...Northwest winds to 30 knots with a few gale force
gusts to 35 knots possible. A slight chance of waterspouts.
Showers. Waves subsiding to 8 to 11 feet occasionally to 14 feet.
.THURSDAY...West winds to 30 knots with a few gale force gusts to
35 knots possible diminishing to 20 to 30 knots in the afternoon.
A slight chance of waterspouts through early afternoon. Showers
likely through early afternoon, then a chance of showers by mid
afternoon. Waves subsiding to 6 to 9 feet occasionally to
11 feet.
.THURSDAY NIGHT...Southwest winds 15 to 25 knots. A chance of
showers through midnight, then showers likely after midnight.
Waves subsiding to 2 to 4 feet.
.FRIDAY...Northwest winds 15 to 25 knots becoming west 20 to
30 knots by mid afternoon. A chance of showers. Waves building to
5 to 8 feet occasionally to 10 feet.
.FRIDAY NIGHT...West winds 15 to 25 knots. A chance of showers.
Waves subsiding to 4 to 7 feet occasionally to 9 feet.
.SATURDAY...Northwest winds 15 to 25 knots. A chance of showers.
Waves subsiding to 2 to 4 feet.
.SATURDAY NIGHT...Northwest winds 10 to 20 knots. A chance of
showers. Waves subsiding to 1 to 3 feet.
.SUNDAY...Northwest winds 10 to 20 knots becoming west 5 to
15 knots. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 10 to 20 knots backing south. Waves
calm to 2 feet.

$$

LSZ267-040800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
401 PM EDT Wed Sep 3 2025

.LATE THIS AFTERNOON...Northwest winds to 30 knots with a few
gale force gusts to 35 knots possible. A chance of showers. Waves
7 to 10 feet occasionally to 13 feet.
.TONIGHT...Northwest winds 20 to 30 knots increasing to 30 knots
with a few gale force gusts to 35 knots possible after midnight,
then backing west late. A slight chance of waterspouts. Showers
likely. Waves building to 8 to 12 feet occasionally to 15 feet.
.THURSDAY...West winds to 30 knots with a few gale force gusts to
35 knots possible diminishing to 20 to 30 knots late. A slight
chance of waterspouts through early afternoon. Showers likely
through early afternoon, then a chance of showers by mid
afternoon. Waves subsiding to 6 to 9 feet occasionally to
11 feet.
.THURSDAY NIGHT...Southwest winds 15 to 25 knots backing south
after midnight. A chance of showers through midnight, then
showers likely after midnight. Waves subsiding to 2 to 4 feet.
.FRIDAY...West winds 15 to 25 knots increasing to gales to
35 knots by mid afternoon. Showers through early afternoon, then
a chance of showers by mid afternoon. Waves building to 5 to
8 feet occasionally to 10 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots diminishing to 15 to
25 knots after midnight. A chance of showers. Waves subsiding to
4 to 7 feet occasionally to 9 feet.
.SATURDAY...West winds 15 to 25 knots veering northwest by mid
afternoon. A chance of showers. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.SATURDAY NIGHT...Northwest winds 10 to 20 knots. A chance of
showers. Waves subsiding to 2 to 4 feet.
.SUNDAY...Northwest winds 10 to 20 knots backing west. A chance
of showers. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 10 to 20 knots backing south. Waves
calm to 2 feet.

$$

LSZ261-040200-
MAFOR 0321/
Superior West 12740 11730 11740 12730 12630. A chance of showers
early this evening. Waves 3 to 6 feet building to 4 to 7 feet,
then subsiding to 3 to 6 feet tonight. Waves 3 to 6 feet
Thursday.

Superior North Central...GALE WARNING IN EFFECT...11756 14746
11740 12640. Waves 7 to 11 feet subsiding to 6 to 9 feet tonight.
Waves 5 to 9 feet Thursday.

Superior South Central 11756 13746 11740 11746 12640. Waves 8 to
12 feet subsiding to 7 to 10 feet tonight. Waves 6 to 10 feet
subsiding to 5 to 8 feet Thursday.

Superior East 11740 13746 12646 12640. Waves 6 to 10 feet
building to 8 to 11 feet tonight. Waves 7 to 11 feet Thursday.

$$

WFO MQT

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weather.gov/mqt/glftable

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weather.gov/greatlakes