Great Lakes Forecast
Issued by NWS

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350
FZUS63 KMQT 182120 CCA
GLFLS

Open Lake Forecast for Lake Superior...CORRECTED
National Weather Service Marquette MI
420 PM EST Tue Nov 18 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 averaging 30.1 inches persists over Lake Superior as a
28.8 inch low retrogrades back into far northern Quebec. 30.2 inch
ridging continues to encompass the Great Lakes basin Wednesday,
shifting into New England Wednesday night and Thursday as a 29.7
inch low develops over northern Ontario. High pressure ridging of
around 30.1 inches develops over the Northern Plains and Upper
Midwest on Friday before moving into the Great Lakes region by
Saturday. Meanwhile, troughing of 29.8 inches moves over Lake
Superior on Saturday before weakening to 29.9 inches over the lake by
Sunday morning.


LSZ162-190900-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
420 PM EST Tue Nov 18 2025 /320 PM CST Tue Nov 18 2025/

.LATE THIS AFTERNOON...East winds 5 to 15 knots. Waves calm to
2 feet.
.TONIGHT...Southwest winds less than 10 knots increasing to 5 to
15 knots by midnight. Waves calm to 2 feet.
.WEDNESDAY...Southwest winds 5 to 15 knots increasing to 10 to
20 knots. A slight chance of rain showers in the afternoon. Waves
building to 1 to 3 feet.
.WEDNESDAY NIGHT...Southwest winds 10 to 20 knots increasing to
15 to 25 knots by midnight, then diminishing to 10 to 20 knots
late. A chance of rain showers in the evening, then rain showers
likely after midnight. Waves building to 2 to 4 feet.
.THURSDAY...West winds 10 to 20 knots increasing to 15 to
25 knots in the afternoon. A chance of rain showers in the
morning. Waves subsiding to 1 to 3 feet.
.THURSDAY NIGHT...West winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. Waves 1 to 3 feet.
.FRIDAY...Northwest winds 10 to 20 knots becoming west 5 to
15 knots in the afternoon. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...West winds 5 to 15 knots backing southwest after
midnight. Waves calm to 2 feet.
.SATURDAY...Southwest winds 10 to 20 knots veering west. Waves
building to 1 to 3 feet, then subsiding to calm to 2 feet.
.SUNDAY...West winds 10 to 20 knots. Waves calm to 2 feet.

$$

LSZ263-190900-
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-
420 PM EST Tue Nov 18 2025

.LATE THIS AFTERNOON...Northwest winds less than 10 knots. Waves
calm to 2 feet.
.TONIGHT...West winds less than 10 knots becoming southwest 5 to
15 knots late. Waves calm to 2 feet.
.WEDNESDAY...Southwest winds 5 to 15 knots increasing to 10 to
20 knots. Waves building to 1 to 3 feet.
.WEDNESDAY NIGHT...Southwest winds 10 to 20 knots increasing to
15 to 25 knots by midnight. A chance of rain showers. Waves
building to 3 to 5 feet occasionally to 7 feet.
.THURSDAY...Southwest winds 15 to 25 knots veering west in the
afternoon. Rain showers likely in the morning, then a slight
chance of rain showers in the afternoon. Waves 3 to 5 feet
occasionally to 7 feet.
.THURSDAY NIGHT...West winds 15 to 25 knots. Waves subsiding to
2 to 4 feet.
.FRIDAY...Northwest winds 15 to 25 knots becoming west 10 to
20 knots in the afternoon. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...West winds 5 to 15 knots backing southwest after
midnight. Waves calm to 2 feet.
.SATURDAY...Southwest winds 15 to 25 knots becoming west 10 to
20 knots. Waves building to 2 to 4 feet, then subsiding to 1 to
3 feet.
.SUNDAY...West winds 15 to 25 knots diminishing to 10 to
20 knots. Waves subsiding to calm to 2 feet, then building to
1 to 3 feet.

$$

LSZ264-190900-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
420 PM EST Tue Nov 18 2025

.LATE THIS AFTERNOON...Northwest winds less than 10 knots. Waves
calm to 2 feet.
.TONIGHT...Northwest winds less than 10 knots becoming west 5 to
15 knots by midnight. Waves calm to 2 feet.
.WEDNESDAY...Southwest winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. Waves building to 1 to 3 feet.
.WEDNESDAY NIGHT...Southwest winds 10 to 20 knots increasing to
15 to 25 knots by midnight. A chance of rain showers. Waves
building to 3 to 5 feet occasionally to 7 feet.
.THURSDAY...Southwest winds 15 to 25 knots veering west in the
afternoon. Rain showers in the morning, then a chance of rain
showers in the afternoon. Waves 3 to 5 feet occasionally to
7 feet.
.THURSDAY NIGHT...Northwest winds 15 to 25 knots backing west
after midnight. Waves building to 3 to 6 feet occasionally to
8 feet.
.FRIDAY...Northwest winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon. Waves subsiding to 1 to 3 feet.
.FRIDAY NIGHT...Northwest winds 5 to 15 knots backing southwest
after midnight. Waves subsiding to calm to 2 feet.
.SATURDAY...Southwest winds 15 to 25 knots becoming west 10 to
20 knots. Waves building to 2 to 4 feet.
.SUNDAY...West winds 15 to 25 knots diminishing to 10 to
20 knots. Waves subsiding to 1 to 3 feet.

$$

LSZ265-190900-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
420 PM EST Tue Nov 18 2025

.LATE THIS AFTERNOON...Northwest winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...Northwest winds 5 to 15 knots backing west by
midnight. Waves calm to 2 feet.
.WEDNESDAY...Southwest winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...Southwest winds 10 to 20 knots increasing to
15 to 25 knots by midnight. A chance of rain showers after
midnight. Waves calm to 2 feet.
.THURSDAY...Southwest winds 15 to 25 knots becoming west 20 to
30 knots in the afternoon. Rain showers likely. Waves building to
2 to 4 feet.
.THURSDAY NIGHT...West winds 20 to 30 knots. Waves 2 to 4 feet.
.FRIDAY...Northwest winds 20 to 30 knots diminishing to 15 to
25 knots in the afternoon. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...Northwest winds 5 to 15 knots backing southwest
after midnight. Waves calm to 2 feet.
.SATURDAY...Southwest winds 10 to 20 knots becoming west 15 to
25 knots. Waves calm to 2 feet.
.SUNDAY...West winds 15 to 25 knots. Waves calm to 2 feet.

$$

LSZ266-190900-
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-
420 PM EST Tue Nov 18 2025

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

$$

LSZ267-190900-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
420 PM EST Tue Nov 18 2025

.LATE THIS AFTERNOON...Northwest winds 10 to 20 knots. Waves calm
to 2 feet.
.TONIGHT...Northwest winds 10 to 20 knots backing west late.
Waves calm to 2 feet.
.WEDNESDAY...West winds 10 to 20 knots backing southwest. Waves
calm to 2 feet.
.WEDNESDAY NIGHT...Southwest winds 10 to 20 knots increasing to
15 to 25 knots by midnight. A slight chance of rain showers after
midnight. Waves building to 2 to 4 feet.
.THURSDAY...Southwest winds 15 to 25 knots increasing to 20 to
30 knots in the afternoon. Rain showers. Waves building to 3 to
5 feet occasionally to 7 feet.
.THURSDAY NIGHT...West winds 20 to 30 knots veering northwest
after midnight. Rain showers likely in the evening, then a chance
of rain showers after midnight. Waves building to 4 to 7 feet
occasionally to 9 feet.
.FRIDAY...Northwest winds 20 to 30 knots. A chance of rain and
snow showers. Waves subsiding to 3 to 6 feet occasionally to
8 feet.
.FRIDAY NIGHT...Northwest winds 10 to 20 knots backing west after
midnight. Waves subsiding to calm to 2 feet.
.SATURDAY...Southwest winds 10 to 20 knots becoming west 15 to
25 knots. A chance of rain showers. Waves building to 2 to
4 feet.
.SUNDAY...West winds 15 to 25 knots diminishing to 10 to
20 knots. A chance of rain showers. Waves 2 to 4 feet.

$$

LSZ261-190300-
MAFOR 1822/
Superior West 11200 11400 13500 13510. Waves 2 feet or less.

Superior North Central 12700 13600 11510 12520. Waves 1 foot or
less tonight. Waves 1 to 3 feet Wednesday.

Superior South Central 12700 13600 13500. Waves 1 foot or less.

Superior East 13700 12600 11610 12510. Waves 2 feet 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