fzus63 kmqt 122001
glfls 
expires:202608130800;;074832

open lake forecast for lake superior
national weather service marquette mi
401 pm 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 afternoon, weak 29.8 inch ridging over lake superior separates 
a 29.5 inch low pressure over the gulf of st. lawrence and a plains 
low of 29.7 inches. this pattern holds, leading to calm open lake 
conditions, 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 over lake superior to follow.




lsz162-130800-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
401 pm edt wed aug 12 2026 /301 pm cdt wed aug 12 2026/

.late this afternoon...south winds 5 to 15 knots. waves calm to
2 feet. 
.tonight...north winds 5 to 15 knots. patchy fog after midnight.
a slight chance of showers after midnight. waves calm to 2 feet. 
.thursday...northeast winds 5 to 15 knots veering east in the
afternoon. a slight chance of showers through early afternoon.
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 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...east winds 10 to 20 knots backing northeast by mid
afternoon. a chance of showers. waves calm to 2 feet. 
.saturday night...north winds 5 to 15 knots backing northwest
after midnight. a chance of showers. waves calm to 2 feet. 
.sunday...west winds 5 to 15 knots veering northwest. waves calm
to 2 feet. 
.monday...southwest winds 5 to 15 knots veering west. waves calm
to 2 feet. 

$$

fzus63 kmqt 122001
glfls 
expires:202608130800;;074833

open lake forecast for lake superior
national weather service marquette mi
401 pm 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 afternoon, weak 29.8 inch ridging over lake superior separates 
a 29.5 inch low pressure over the gulf of st. lawrence and a plains 
low of 29.7 inches. this pattern holds, leading to calm open lake 
conditions, 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 over lake superior to follow.




lsz263-130800-
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 wed aug 12 2026

.late this afternoon...southwest winds 5 to 15 knots. waves calm
to 2 feet. 
.tonight...west winds less than 10 knots veering north after
midnight. waves calm to 2 feet. 
.thursday...north winds less than 10 knots becoming northeast
5 to 15 knots in the afternoon, then veering east late. a slight
chance of showers through early afternoon. waves calm to 2 feet. 
.thursday night...northeast winds less than 10 knots increasing
to 5 to 15 knots late. 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. waves calm to 2 feet. 
.saturday night...northeast winds 5 to 15 knots backing northwest
after midnight. a chance of showers. waves calm to 2 feet. 
.sunday...west winds 5 to 15 knots. waves calm to 2 feet. 
.monday...west winds 10 to 20 knots backing southwest. waves calm
to 2 feet. 

$$