fzus63 kmqt 212001
glfls 
expires:202607220800;;366727

open lake forecast for lake superior
national weather service marquette mi
401 pm edt tue jul 21 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... 

heights continue to rise over the lake this evening into tonight as 
29.3 inch low pressure east of james bay continues to track through 
northern quebec and ridging over the northern plains expands 
eastward. the ridge over lake superior becomes maximized at 30.1 
inches over the western lake on wednesday before the high flattens 
and moves east towards new england thursday into friday morning. 
while ridging of around 30.0 inches looks to remain over lake 
superior on thursday, a weak 29.9 to 30.0 inch low could move over 
the northwestern half of the lake by thursday night into friday 
morning. as a low around 29.3 inches lifts from far northern ontario 
into hudson bay friday night into saturday morning, expect troughing 
of around 29.8 inches to move into lake superior in response by 
saturday morning. troughing of at least 29.8 inches looks to remain 
over the lake for the rest of the day. 




lsz162-220800-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
401 pm edt tue jul 21 2026 /301 pm cdt tue jul 21 2026/

.late this afternoon...north winds 10 to 20 knots. waves calm to
2 feet. 
.tonight...northwest winds 10 to 20 knots. waves calm to 2 feet. 
.wednesday...west winds 5 to 15 knots backing southwest in the
afternoon, then increasing to 10 to 20 knots late. waves building
to 1 to 3 feet. 
.wednesday night...southwest winds 5 to 15 knots. waves subsiding
to calm to 2 feet. 
.thursday...southwest winds 10 to 20 knots. waves building to
1 to 3 feet. 
.thursday night...southwest winds 10 to 20 knots. waves subsiding
to calm to 2 feet. 
.friday...southwest winds 15 to 25 knots increasing to 20 to
30 knots by mid afternoon. waves building to 2 to 4 feet, then
subsiding to 1 to 3 feet. 
.friday night...southwest winds 20 to 30 knots increasing to
gales to 35 knots after midnight. a chance of showers. waves
subsiding to calm to 2 feet, then building to 2 to 4 feet. 
.saturday...southwest winds 20 to 30 knots becoming north 5 to
15 knots. a chance of showers. waves subsiding to calm to 2 feet.
.sunday...east winds 5 to 15 knots backing northeast. waves calm
to 2 feet. 

$$

fzus63 kmqt 212001
glfls 
expires:202607220800;;366728

open lake forecast for lake superior
national weather service marquette mi
401 pm edt tue jul 21 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... 

heights continue to rise over the lake this evening into tonight as 
29.3 inch low pressure east of james bay continues to track through 
northern quebec and ridging over the northern plains expands 
eastward. the ridge over lake superior becomes maximized at 30.1 
inches over the western lake on wednesday before the high flattens 
and moves east towards new england thursday into friday morning. 
while ridging of around 30.0 inches looks to remain over lake 
superior on thursday, a weak 29.9 to 30.0 inch low could move over 
the northwestern half of the lake by thursday night into friday 
morning. as a low around 29.3 inches lifts from far northern ontario 
into hudson bay friday night into saturday morning, expect troughing 
of around 29.8 inches to move into lake superior in response by 
saturday morning. troughing of at least 29.8 inches looks to remain 
over the lake for the rest of the day. 




lsz263-220800-
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 jul 21 2026

.late this afternoon...north winds 10 to 20 knots. waves 2 to
4 feet. 
.tonight...northwest winds 10 to 20 knots diminishing to 5 to
15 knots after midnight. waves subsiding to calm to 2 feet. 
.wednesday...northwest winds 5 to 15 knots backing west in the
afternoon, then becoming southwest 10 to 20 knots late. waves
building to 1 to 3 feet. 
.wednesday night...southwest winds 10 to 20 knots becoming west
5 to 15 knots after midnight, then increasing to 10 to 20 knots
late. waves subsiding to calm to 2 feet, then building to 1 to
3 feet. 
.thursday...southwest winds 15 to 25 knots. waves building to
2 to 4 feet. 
.thursday night...southwest winds 10 to 20 knots increasing to
15 to 25 knots after midnight. waves subsiding to 1 to 3 feet. 
.friday...southwest winds 20 to 30 knots. waves building to 2 to
4 feet, then subsiding to 1 to 3 feet. 
.friday night...southwest winds 20 to 30 knots increasing to
gales to 35 knots after midnight. a chance of showers after
midnight. waves building to 2 to 4 feet. 
.saturday...southwest gales to 35 knots becoming north 5 to
15 knots. a chance of showers. waves subsiding to calm to 2 feet.
.sunday...east winds 5 to 15 knots. a chance of showers. waves
calm to 2 feet. 

$$