778
FZUS63 KMQT 192001
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
400 PM EDT Thu Mar 19 2026

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...

Weak ridging around 30.1 inches over Lake Superior this afternoon
gives way a clipper low moving across the lake tonight into early
Friday at around 29.7 inches. While another low moves through
northern Ontario toward the north shores of Lake Superior Friday
night, another low stretches into the Northern Plains around the
same time. Together, these lows are expected to bring about
troughing of around around 29.8 inch over Lake Superior on Saturday
into Sunday. Behind the troughing, 30.4 inch ridging builds into the
Great Lakes and Northern Plains by Monday. A 29.9 inch clipper low
tracking across northern Ontario on Tuesday briefly extends a 30.0
inch trough over the lake. A 30.5 inch high quickly follows behind
it for Wednesday.


LSZ162-200800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
400 PM EDT Thu Mar 19 2026 /300 PM CDT Thu Mar 19 2026/

.LATE THIS AFTERNOON...East winds 10 to 20 knots. A slight chance
of rain and snow showers. Waves calm to 2 feet.
.TONIGHT...East winds 10 to 20 knots veering southwest after
midnight, then veering west late. A chance of freezing rain, snow
and rain showers through midnight. Waves calm to 2 feet.
.FRIDAY...West winds 5 to 15 knots. Waves calm to 2 feet.
.FRIDAY NIGHT...West winds 5 to 15 knots veering northeast late.
Waves calm to 2 feet.
.SATURDAY...East winds 5 to 15 knots becoming northeast 10 to
20 knots by mid afternoon. A chance of rain and snow showers.
Waves building to 1 to 3 feet.
.SATURDAY NIGHT...Northeast winds 15 to 25 knots. A chance of
snow showers, possibly mixed with rain. Waves building to 4 to
7 feet occasionally to 9 feet.
.SUNDAY...Northeast winds 15 to 25 knots diminishing to 10 to
20 knots by mid afternoon. A chance of snow showers. Waves
subsiding to 3 to 5 feet occasionally to 7 feet.
.SUNDAY NIGHT...Northeast winds 10 to 20 knots becoming northwest
5 to 15 knots after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots increasing to 20 to
30 knots. Waves building to 3 to 5 feet occasionally to 7 feet.
.TUESDAY...West winds 15 to 25 knots becoming northeast 10 to
20 knots. Waves subsiding to calm to 2 feet, then building to
3 to 5 feet occasionally to 7 feet.

$$

LSZ263-200800-
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-
400 PM EDT Thu Mar 19 2026

.LATE THIS AFTERNOON...East winds 5 to 15 knots. A slight chance
of rain and snow showers. Waves calm to 2 feet.
.TONIGHT...Southeast winds 10 to 20 knots veering southwest after
midnight, then becoming west 5 to 15 knots late. Snow showers,
possibly mixed with freezing rain through midnight. A chance of
rain showers. Waves building to 2 to 4 feet, then subsiding to
1 to 3 feet.
.FRIDAY...Northwest winds 5 to 15 knots backing west in the
afternoon. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...West winds 5 to 15 knots veering northeast late.
Waves calm to 2 feet.
.SATURDAY...East winds 5 to 15 knots increasing to 15 to 25 knots
by mid afternoon. A chance of snow showers, possibly mixed with
rain. Waves building to 1 to 3 feet.
.SATURDAY NIGHT...Northeast winds 15 to 25 knots. A chance of
rain showers through midnight. A chance of snow showers. Waves
building to 5 to 8 feet occasionally to 10 feet.
.SUNDAY...Northeast winds 20 to 30 knots diminishing to 15 to
25 knots by mid afternoon. Freezing spray through early
afternoon. A chance of snow showers. Waves subsiding to 3 to
5 feet occasionally to 7 feet.
.SUNDAY NIGHT...Northeast winds 5 to 15 knots backing north after
midnight. Waves subsiding to 2 to 4 feet.
.MONDAY...Northwest winds 10 to 20 knots becoming southwest 20 to
30 knots. Waves subsiding to calm to 2 feet, then building to
5 to 8 feet occasionally to 10 feet.
.TUESDAY...West winds 20 to 30 knots becoming northeast 15 to
25 knots. Waves subsiding to 1 to 3 feet, then building to 4 to
7 feet occasionally to 9 feet.

$$

LSZ264-200800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
400 PM EDT Thu Mar 19 2026

.LATE THIS AFTERNOON...Southeast winds 5 to 15 knots. A slight
chance of snow showers. Waves calm to 2 feet.
.TONIGHT...Southeast winds 15 to 25 knots veering south after
midnight, then becoming west 10 to 20 knots late. Snow showers
through midnight. A chance of rain showers. A chance of snow
showers after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet.
.FRIDAY...North winds 5 to 15 knots backing west late. Waves
subsiding to calm to 2 feet.
.FRIDAY NIGHT...West winds 5 to 15 knots veering north late.
Waves calm to 2 feet.
.SATURDAY...East winds 5 to 15 knots increasing to 10 to 20 knots
by mid afternoon. A chance of rain showers through early
afternoon. A chance of snow showers. Waves building to 1 to
3 feet.
.SATURDAY NIGHT...Northeast winds 15 to 25 knots increasing to
20 to 30 knots after midnight. A chance of snow showers. Freezing
spray after midnight. Waves building to 5 to 8 feet occasionally
to 10 feet.
.SUNDAY...Northeast winds 20 to 30 knots diminishing to 15 to
25 knots by mid afternoon. Freezing spray. Waves subsiding to
3 to 5 feet occasionally to 7 feet.
.SUNDAY NIGHT...Northeast winds 5 to 15 knots backing north after
midnight. Waves subsiding to 2 to 4 feet.
.MONDAY...Northwest winds 5 to 15 knots becoming southwest gales
to 35 knots. Waves subsiding to calm to 2 feet, then building to
6 to 9 feet occasionally to 11 feet.
.TUESDAY...West gales to 35 knots becoming northeast 20 to
30 knots. Freezing spray. Waves subsiding to 3 to 5 feet
occasionally to 7 feet, then building to 5 to 8 feet occasionally
to 10 feet.

$$

LSZ265-200800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
400 PM EDT Thu Mar 19 2026

.LATE THIS AFTERNOON...Southeast winds 10 to 20 knots. A slight
chance of snow showers. Waves calm to 2 feet.
.TONIGHT...Southeast winds 15 to 25 knots increasing to 20 to
30 knots after midnight, then becoming west 15 to 25 knots late.
Rain showers likely, possibly mixed with freezing rain through
midnight. Snow showers. A chance of rain showers after midnight.
Waves building to 3 to 5 feet occasionally to 7 feet, then
subsiding to 1 to 3 feet.
.FRIDAY...Northwest winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then backing west late. Waves
subsiding to calm to 2 feet.
.FRIDAY NIGHT...West winds 10 to 20 knots. Waves calm to 2 feet.
.SATURDAY...East winds 10 to 20 knots increasing to 15 to
25 knots by mid afternoon. A slight chance of rain showers
through early afternoon. A chance of snow showers. Waves building
to 1 to 3 feet.
.SATURDAY NIGHT...Northeast winds 20 to 30 knots. A chance of
snow showers. Waves building to 5 to 8 feet occasionally to
10 feet.
.SUNDAY...Northeast gales to 35 knots diminishing to 20 to
30 knots by mid afternoon. Freezing spray through early
afternoon. A chance of snow showers. Waves building to 6 to
9 feet occasionally to 11 feet, then subsiding to 4 to 7 feet
occasionally to 9 feet.
.SUNDAY NIGHT...North winds 15 to 25 knots. Waves subsiding to
3 to 6 feet occasionally to 8 feet.
.MONDAY...Northwest winds 10 to 20 knots becoming southwest gales
to 35 knots. Waves subsiding to calm to 2 feet, then building to
4 to 7 feet occasionally to 9 feet.
.TUESDAY...West gales to 35 knots becoming northwest 20 to
30 knots. Freezing spray. Waves subsiding to 2 to 4 feet, then
building to 6 to 9 feet occasionally to 11 feet.

$$

LSZ266-200800-
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-
400 PM EDT Thu Mar 19 2026

.LATE THIS AFTERNOON...Southeast winds 5 to 15 knots. A slight
chance of snow showers. Waves calm to 2 feet.
.TONIGHT...Southeast winds 15 to 25 knots increasing to 20 to
30 knots after midnight, then becoming south 15 to 25 knots late.
A slight chance of freezing rain through midnight. Snow showers.
A slight chance of rain showers 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 calm to 2 feet.
.FRIDAY NIGHT...West winds 10 to 20 knots veering northwest late.
Waves calm to 2 feet.
.SATURDAY...Southeast winds 10 to 20 knots becoming east 15 to
25 knots by mid afternoon. A chance of rain showers through early
afternoon. A chance of snow showers. Waves building to 1 to
3 feet.
.SATURDAY NIGHT...East winds 15 to 25 knots becoming northeast
20 to 30 knots after midnight. A chance of snow showers. Waves
building to 5 to 8 feet occasionally to 10 feet.
.SUNDAY...Northeast gales to 35 knots diminishing to 20 to
30 knots by mid afternoon. Freezing spray through early
afternoon. A chance of snow showers. Waves building to 6 to
9 feet occasionally to 11 feet, then subsiding to 4 to 7 feet
occasionally to 9 feet.
.SUNDAY NIGHT...Northeast winds 15 to 25 knots backing north
after midnight. Waves subsiding to 3 to 6 feet occasionally to
8 feet.
.MONDAY...Northwest winds 10 to 20 knots becoming south gales to
40 knots. Waves subsiding to 1 to 3 feet, then building to 9 to
12 feet occasionally to 15 feet.
.TUESDAY...West gales to 40 knots becoming north 20 to 30 knots.
Freezing spray. Waves subsiding to 5 to 8 feet occasionally to
10 feet, then building to 6 to 9 feet occasionally to 11 feet.

$$

LSZ267-200800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
400 PM EDT Thu Mar 19 2026

.LATE THIS AFTERNOON...Southeast winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...Southeast winds 10 to 20 knots becoming south 15 to
25 knots late. Snow showers. A slight chance of rain showers
after midnight. Waves building to 2 to 4 feet, then subsiding to
1 to 3 feet.
.FRIDAY...Northwest winds 10 to 20 knots. Waves subsiding to calm
to 2 feet.
.FRIDAY NIGHT...West winds 10 to 20 knots. Waves calm to 2 feet.
.SATURDAY...Southeast winds 10 to 20 knots backing east by mid
afternoon. A chance of snow showers. Waves building to 1 to
3 feet, then subsiding to calm to 2 feet.
.SATURDAY NIGHT...East winds 15 to 25 knots becoming northeast
20 to 30 knots after midnight. A chance of snow showers. Waves
building to 3 to 6 feet occasionally to 8 feet.
.SUNDAY...Northeast winds 20 to 30 knots diminishing to 15 to
25 knots by mid afternoon. Freezing spray through early
afternoon. A chance of snow showers. Waves subsiding to 3 to
5 feet occasionally to 7 feet.
.SUNDAY NIGHT...Northeast winds 15 to 25 knots becoming north
10 to 20 knots after midnight. Waves subsiding to 2 to 4 feet,
then building to 3 to 5 feet occasionally to 7 feet.
.MONDAY...North winds 10 to 20 knots becoming south gales to
35 knots. Freezing spray. A chance of snow showers. Waves
subsiding to calm to 2 feet, then building to 7 to 10 feet
occasionally to 13 feet.
.TUESDAY...West gales to 35 knots becoming northwest 15 to
25 knots. A chance of snow showers. Freezing spray. Waves
building to 9 to 12 feet occasionally to 15 feet, then subsiding
to 4 to 7 feet occasionally to 9 feet.

$$

LSZ261-200200-
MAFOR 1921/
Superior West 11210 11310 11510 12610 11700 12600. A chance of
snow showers this evening. Waves 2 feet or less.

Superior North Central 11310 12337 11437 11620 11820 12710. A
chance of light freezing rain overnight. Waves 2 feet or less
building to 3 to 5 feet tonight. Waves 3 to 5 feet subsiding to 2
to 4 feet Friday.

Superior South Central 11320 11330 11337 11437 11520 12720 11710.
A chance of rain showers overnight. Waves 2 feet or less building
to 3 to 5 feet tonight. Waves 2 to 4 feet subsiding to 1 to 3
feet Friday.

Superior East 11400 11320 12337 11420 11720 11810 11710. A chance
of light freezing rain overnight. Waves 1 to 2 feet building to 3
to 5 feet tonight. Waves 2 to 4 feet subsiding to 1 to 3 feet
Friday.

$$

WFO MQT

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weather.gov/mqt/glftable

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weather.gov/greatlakes