fzus63 kmqt 120801
glfls 
expires:202608122000;;045624

open lake forecast for lake superior
national weather service marquette mi
401 am edt wed aug 12 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...

this morning, 29.5 inch low pressure is over the gulf of st lawrence 
and deepens to 29.5 inches while a plains low of 29.7 inches is only 
separated from the first low by weak 29.8-29.9 inch ridging over 
lake superior. this pattern holds until thursday morning, when a 
30.2 inch high over the canadian rockies begins to extend stronger 
ridging over lake superior before eventually becoming centered over 
the lake at 30.2 inches friday afternoon. a 29.9 inch trough then 
moves over the western end of the lake saturday afternoon as the 
30.2 inch high moves over the lower great lakes. this trough 
consolidates to a 29.8 inch low as it passes over lake superior, 
reaching ontario by sunday afternoon, with 30.1 inch ridging to 
follow.




lsz162-122000-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
401 am edt wed aug 12 2026 /301 am cdt wed aug 12 2026/

.early this morning...north winds less than 10 knots. patchy fog.
waves calm to 2 feet. 
.today...northwest winds less than 10 knots becoming south 5 to
15 knots in the afternoon. patchy dense fog through early
afternoon. waves calm to 2 feet. 
.tonight...northeast winds 5 to 15 knots backing north after
midnight, then veering northeast late. a chance of showers. waves
calm to 2 feet. 
.thursday...northeast winds 5 to 15 knots veering east late.
waves calm to 2 feet. 
.thursday night...northeast winds 5 to 15 knots. waves calm to
2 feet. 
.friday...northeast winds 10 to 20 knots increasing to 15 to
25 knots by mid afternoon. waves building to 2 to 4 feet, then
subsiding to 1 to 3 feet. 
.friday night...northeast winds 15 to 25 knots diminishing to
5 to 15 knots after midnight. waves subsiding to calm to 2 feet. 
.saturday...northeast winds 5 to 15 knots backing north. a chance
of showers. waves calm to 2 feet. 
.sunday...west winds 5 to 15 knots veering northwest. waves calm
to 2 feet. 

$$

fzus63 kmqt 120801
glfls 
expires:202608122000;;045625

open lake forecast for lake superior
national weather service marquette mi
401 am edt wed aug 12 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...

this morning, 29.5 inch low pressure is over the gulf of st lawrence 
and deepens to 29.5 inches while a plains low of 29.7 inches is only 
separated from the first low by weak 29.8-29.9 inch ridging over 
lake superior. this pattern holds until thursday morning, when a 
30.2 inch high over the canadian rockies begins to extend stronger 
ridging over lake superior before eventually becoming centered over 
the lake at 30.2 inches friday afternoon. a 29.9 inch trough then 
moves over the western end of the lake saturday afternoon as the 
30.2 inch high moves over the lower great lakes. this trough 
consolidates to a 29.8 inch low as it passes over lake superior, 
reaching ontario by sunday afternoon, with 30.1 inch ridging to 
follow.




lsz263-122000-
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 am edt wed aug 12 2026

.early this morning...northwest winds less than 10 knots. waves
calm to 2 feet. 
.today...northwest winds less than 10 knots increasing to 5 to
15 knots in the afternoon, then backing south late. waves calm to
2 feet. 
.tonight...east winds less than 10 knots backing north after
midnight, then veering northeast late. a slight chance of showers
after midnight. waves calm to 2 feet. 
.thursday...northeast winds less than 10 knots increasing to 5 to
15 knots in the afternoon. waves calm to 2 feet. 
.thursday night...northeast winds less than 10 knots increasing
to 5 to 15 knots after midnight. waves calm to 2 feet. 
.friday...northeast winds 5 to 15 knots increasing to 15 to
25 knots by mid afternoon. waves calm to 2 feet. 
.friday night...east winds 10 to 20 knots diminishing to 5 to
15 knots after midnight. waves calm to 2 feet. 
.saturday...east winds 5 to 15 knots backing northwest. a chance
of showers. waves calm to 2 feet. 
.sunday...west winds 5 to 15 knots. waves calm to 2 feet. 

$$