618
FZUS63 KMQT 100207 CCA
GLFLS

Open Lake Forecast for Lake Superior...CORRECTED
National Weather Service Marquette MI
1007 PM EDT Thu Oct 9 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...

30.5 inch high pressure continues to slide eastward this evening,
becoming centered over New England later tonight. This allows a 30.0
inch trough to move into the Upper Great Lakes as a 29.4 inch low
moves over Hudson Bay. Along this trough, a 29.9 inch low develops
near Thunder Bay, then moves over Lake Superior Friday afternoon and
evening. The low then drops into Lower Michigan Friday night and
Saturday while 30.2 inch ridging builds over Lake Superior. This
ridge gradually weakens through the weekend as the next system
organizes upstream in the Northern Plains. By early Monday, a
weakening 29.4 inch low pressure moves from Manitoba into northern
Ontario, causing a 29.8 to 29.9 inch trough to move over Lake
Superior before ridging returns late Monday into Tuesday, building
to 30.4 inches by Tuesday morning.


LSZ162-100800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1007 PM EDT Thu Oct 9 2025 /907 PM CDT Thu Oct 9 2025/

.REST OF TONIGHT...South winds 15 to 25 knots veering southwest
after midnight. A chance of showers. Waves 2 to 4 feet building
to 3 to 6 feet occasionally to 8 feet.
.FRIDAY...Northwest winds 20 to 30 knots. A slight chance of
showers. Waves subsiding to 2 to 4 feet.
.FRIDAY NIGHT...North winds 15 to 25 knots diminishing to 10 to
20 knots after midnight, then veering northeast late. Waves
subsiding to calm to 2 feet.
.SATURDAY...East winds 5 to 15 knots. Waves calm to 2 feet.
.SATURDAY NIGHT...East winds 10 to 20 knots veering south after
midnight. Waves building to 2 to 4 feet.
.SUNDAY...Southeast winds 10 to 20 knots increasing to 15 to
25 knots by mid afternoon. A chance of showers. Waves building to
3 to 5 feet occasionally to 7 feet.
.SUNDAY NIGHT...Southeast winds 20 to 30 knots veering south
after midnight. Showers. Waves building to 4 to 7 feet
occasionally to 9 feet.
.MONDAY...Southwest winds 20 to 30 knots becoming west 15 to
25 knots. A chance of showers. Waves subsiding to 1 to 3 feet.
.TUESDAY...Northwest winds 10 to 20 knots veering north. Waves
subsiding to calm to 2 feet.

$$

LSZ263-100800-
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-
1007 PM EDT Thu Oct 9 2025

...GALE WARNING IN EFFECT FROM 8 AM EDT FRIDAY THROUGH FRIDAY
EVENING...

.REST OF TONIGHT...South winds 15 to 25 knots becoming southwest
20 to 30 knots after midnight. A chance of showers. Waves 2 to
4 feet building to 3 to 6 feet occasionally to 8 feet.
.FRIDAY...West gales to 35 knots veering northwest in the
afternoon. A chance of showers. Waves building to 4 to 7 feet
occasionally to 9 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.
.FRIDAY NIGHT...North winds 20 to 30 knots diminishing to 15 to
25 knots after midnight, then becoming northeast 10 to 20 knots
late. Waves subsiding to 2 to 4 feet.
.SATURDAY...East winds 5 to 15 knots. Waves subsiding to calm to
2 feet.
.SATURDAY NIGHT...Southeast winds 10 to 20 knots becoming south
15 to 25 knots after midnight. Waves building to 2 to 4 feet.
.SUNDAY...Southeast winds 15 to 25 knots increasing to 20 to
30 knots by mid afternoon. Waves building to 4 to 7 feet
occasionally to 9 feet.
.SUNDAY NIGHT...Southeast gales to 35 knots veering south after
midnight. A chance of showers through midnight, then showers
likely after midnight. Waves building to 4 to 8 feet occasionally
to 10 feet.
.MONDAY...Southwest gales to 35 knots becoming west 20 to
30 knots. Waves building to 5 to 8 feet occasionally to 10 feet,
then subsiding to 3 to 6 feet occasionally to 8 feet.
.TUESDAY...Northwest winds 15 to 25 knots becoming north 10 to
20 knots. Waves subsiding to calm to 2 feet.

$$

LSZ264-100800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1007 PM EDT Thu Oct 9 2025

...GALE WARNING IN EFFECT FROM 8 AM EDT FRIDAY THROUGH FRIDAY
EVENING...

.REST OF TONIGHT...South winds 15 to 25 knots increasing to 20 to
30 knots after midnight. A chance of showers by midnight, then
showers after midnight. Waves 3 to 5 feet occasionally to 7 feet
building to 4 to 7 feet occasionally to 9 feet.
.FRIDAY...West gales to 35 knots veering north late. Showers
likely through early afternoon, then a chance of showers by mid
afternoon. Waves 4 to 7 feet occasionally to 9 feet.
.FRIDAY NIGHT...North winds 20 to 30 knots diminishing to 15 to
25 knots after midnight, then becoming northeast 10 to 20 knots
late. Waves subsiding to 2 to 4 feet.
.SATURDAY...East winds 5 to 15 knots. Waves subsiding to calm to
2 feet.
.SATURDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. Waves building to 2 to 4 feet.
.SUNDAY...South winds 20 to 30 knots becoming southeast gales to
35 knots by mid afternoon. Waves building to 6 to 9 feet
occasionally to 11 feet.
.SUNDAY NIGHT...Southeast gales to 35 knots veering south after
midnight. A chance of showers. Waves building to 7 to 10 feet
occasionally to 13 feet.
.MONDAY...South gales to 35 knots becoming west 20 to 30 knots.
Showers likely. Waves subsiding to 4 to 7 feet occasionally to
9 feet.
.TUESDAY...Northwest winds 20 to 30 knots becoming north 10 to
20 knots. Waves subsiding to 1 to 3 feet.

$$

LSZ265-100800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1007 PM EDT Thu Oct 9 2025

...GALE WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
EVENING...

.REST OF TONIGHT...South winds 20 to 30 knots veering southwest
late. Showers after midnight. Waves 3 to 5 feet occasionally to
7 feet subsiding to 2 to 4 feet.
.FRIDAY...Southwest gales to 35 knots becoming northwest gales to
40 knots late. A slight chance of thunderstorms through early
afternoon. Showers. Waves building to 3 to 5 feet occasionally to
7 feet, then subsiding to 2 to 4 feet.
.FRIDAY NIGHT...North gales to 40 knots diminishing to 20 to
30 knots late. A chance of showers through midnight. Waves
subsiding to 3 to 6 feet occasionally to 8 feet, then building to
4 to 7 feet occasionally to 9 feet.
.SATURDAY...Northeast winds 10 to 20 knots veering east by mid
afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...Southeast winds 10 to 20 knots. Waves calm to
2 feet.
.SUNDAY...Southeast winds 15 to 25 knots increasing to 20 to
30 knots by mid afternoon. Waves building to 2 to 4 feet.
.SUNDAY NIGHT...Southeast gales to 35 knots veering south after
midnight. A chance of showers. Waves building to 3 to 6 feet
occasionally to 8 feet.
.MONDAY...South gales to 35 knots becoming west 20 to 30 knots.
Showers likely. Waves subsiding to calm to 2 feet, then building
to 1 to 3 feet.
.TUESDAY...Northwest winds 20 to 30 knots becoming north 10 to
20 knots. Waves subsiding to calm to 2 feet.

$$

LSZ266-100800-
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-
1007 PM EDT Thu Oct 9 2025

...GALE WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
EVENING...

.REST OF TONIGHT...South winds 20 to 30 knots. Showers after
midnight. Waves 4 to 8 feet occasionally to 10 feet.
.FRIDAY...Southwest gales to 35 knots becoming northwest gales to
40 knots late. Showers and a slight chance of thunderstorms.
Waves subsiding to 4 to 7 feet occasionally to 9 feet.
.FRIDAY NIGHT...North gales to 35 knots diminishing to 20 to
30 knots after midnight. A chance of showers through midnight.
Waves building to 5 to 8 feet occasionally to 10 feet, then
subsiding to 3 to 6 feet occasionally to 8 feet.
.SATURDAY...Northeast winds 10 to 20 knots becoming east 5 to
15 knots by mid afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...Southeast winds 5 to 15 knots increasing to
10 to 20 knots after midnight. Waves building to 2 to 4 feet.
.SUNDAY...Southeast winds 15 to 25 knots increasing to gales to
35 knots by mid afternoon. Waves building to 5 to 8 feet
occasionally to 10 feet.
.SUNDAY NIGHT...Southeast gales to 35 knots veering south after
midnight. A chance of showers. Waves building to 7 to 10 feet
occasionally to 13 feet.
.MONDAY...South gales to 35 knots becoming northwest 20 to
30 knots. Showers likely. Waves subsiding to 4 to 8 feet
occasionally to 10 feet.
.TUESDAY...Northwest winds 15 to 25 knots veering north. Waves
subsiding to 2 to 4 feet.

$$

LSZ267-100800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1007 PM EDT Thu Oct 9 2025

.REST OF TONIGHT...South winds 15 to 25 knots increasing to 20 to
30 knots late. A chance of showers after midnight. Waves 3 to
6 feet occasionally to 8 feet.
.FRIDAY...South winds to 30 knots with a few gale force gusts to
35 knots possible veering southwest in the afternoon, then
becoming west 20 to 30 knots late. Showers. A slight chance of
thunderstorms by mid afternoon. Waves building to 5 to 8 feet
occasionally to 10 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.
.FRIDAY NIGHT...North winds 15 to 25 knots veering northeast
after midnight, then increasing to 20 to 30 knots late. A chance
of showers through midnight. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.SATURDAY...Northeast winds 10 to 20 knots becoming east 5 to
15 knots by mid afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...Southeast winds 10 to 20 knots increasing to
15 to 25 knots after midnight. Waves building to 1 to 3 feet.
.SUNDAY...Southeast winds 15 to 25 knots increasing to 20 to
30 knots by mid afternoon. Waves building to 3 to 5 feet
occasionally to 7 feet.
.SUNDAY NIGHT...Southeast winds 20 to 30 knots. Waves building to
3 to 6 feet occasionally to 8 feet.
.MONDAY...South winds 15 to 25 knots veering west. Showers
likely, then a chance of showers. Waves subsiding to 2 to 4 feet,
then building to 4 to 7 feet occasionally to 9 feet.
.TUESDAY...Northwest winds 15 to 25 knots veering north. Waves
building to 5 to 8 feet occasionally to 10 feet, then subsiding
to 2 to 4 feet.

$$

LSZ261-100800-
MAFOR 1003/
Superior West...GALE WARNING IN EFFECT...11430 12540 11640 13740
19750 11830. A chance of showers overnight. Waves 3 to 6 feet
overnight and Friday. Waves 3 to 5 feet subsiding to 2 to 4 feet
Friday evening.

Superior North Central...GALE WARNING IN EFFECT...11440 11546
11446 11546 11656 11750 11850 11840. Waves 3 to 6 feet overnight.
Waves 5 to 8 feet Friday and Friday evening.

Superior South Central...GALE WARNING IN EFFECT...11440 11530
12546 12656 11756 11850. Waves 3 to 6 feet overnight and Friday.
Waves 4 to 7 feet Friday evening.

Superior East...GALE WARNING IN EFFECT...11440 11430 11440 11446
11556 11546 11740 11840. Waves 3 to 6 feet building to 4 to 7
feet overnight. Waves 5 to 8 feet Friday and Friday evening.

$$

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