fzus63 kmqt 180801
glfls 
expires:202603182000;;888964

open lake forecast for lake superior
national weather service marquette mi
400 am edt wed mar 18 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...

a weakening 29.7 inch clipper low will move across the canadian 
prairies and northern ontario tonight into wednesday. behind this 
low, weak ridging of around 30.1 inches returns over lake superior 
on thursday ahead of another clipper low moving through the lake 
thursday night into early friday at around 29.8 inches. while a low 
moves through ontario to near james bay friday night, another low 
will stretch into the plains. together, this results in around 29.7 
inch troughing over the lake late saturday into sunday. behind the 
trough, 30.4 inch ridging will stretch into the great lakes and 
northern plains to begin next week.



lsz162-182000-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
400 am edt wed mar 18 2026 /300 am cdt wed mar 18 2026/

.early this morning...southwest winds 15 to 25 knots. a slight
chance of snow showers. waves 3 to 5 feet occasionally to 7 feet.
.today...southwest winds 15 to 25 knots diminishing to 10 to
20 knots late. a slight chance of snow showers through early
afternoon. waves subsiding to 2 to 4 feet. 
.tonight...southwest winds 5 to 15 knots veering northwest late.
a slight chance of rain showers. a slight chance of snow showers
after midnight. waves subsiding to calm to 2 feet. 
.thursday...northeast winds 5 to 15 knots veering southeast in
the afternoon, then veering south late. waves calm to 2 feet. 
.thursday night...south winds 5 to 15 knots veering southwest
after midnight. a chance of snow showers through midnight. a
chance of rain showers. waves calm to 2 feet. 
.friday...north winds 5 to 15 knots increasing to 10 to 20 knots
by mid afternoon. waves calm to 2 feet. 
.friday night...west winds 10 to 20 knots. waves building to 1 to
3 feet. 
.saturday...northeast winds 10 to 20 knots increasing to 15 to
25 knots. a chance of rain showers. a chance of snow showers.
waves building to 3 to 5 feet occasionally to 7 feet. 
.sunday...northeast winds 15 to 25 knots becoming north 5 to
15 knots. waves subsiding to calm to 2 feet. 

$$

fzus63 kmqt 180801
glfls 
expires:202603182000;;888965

open lake forecast for lake superior
national weather service marquette mi
400 am edt wed mar 18 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...

a weakening 29.7 inch clipper low will move across the canadian 
prairies and northern ontario tonight into wednesday. behind this 
low, weak ridging of around 30.1 inches returns over lake superior 
on thursday ahead of another clipper low moving through the lake 
thursday night into early friday at around 29.8 inches. while a low 
moves through ontario to near james bay friday night, another low 
will stretch into the plains. together, this results in around 29.7 
inch troughing over the lake late saturday into sunday. behind the 
trough, 30.4 inch ridging will stretch into the great lakes and 
northern plains to begin next week.



lsz263-182000-
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 am edt wed mar 18 2026

.early this morning...south winds 15 to 25 knots. a chance of
snow showers. waves 3 to 5 feet occasionally to 7 feet. 
.today...southwest winds 10 to 20 knots. a chance of snow showers
through early afternoon. waves 3 to 5 feet occasionally to
7 feet. 
.tonight...west winds 5 to 15 knots veering north late. waves
subsiding to calm to 2 feet. 
.thursday...northeast winds 5 to 15 knots becoming east less than
10 knots in the afternoon, then becoming south 5 to 15 knots
late. waves calm to 2 feet. 
.thursday night...south winds 5 to 15 knots veering southwest
after midnight. a chance of rain showers, possibly mixed with
snow. waves calm to 2 feet. 
.friday...west winds 5 to 15 knots veering northwest by mid
afternoon. waves calm to 2 feet. 
.friday night...west winds 5 to 15 knots increasing to 10 to
20 knots after midnight. waves building to 2 to 4 feet. 
.saturday...northeast winds 15 to 25 knots increasing to 20 to
30 knots. a chance of rain showers. a chance of snow showers.
waves building to 4 to 7 feet occasionally to 9 feet. 
.sunday...northeast winds 20 to 30 knots becoming north 10 to
20 knots. waves subsiding to 1 to 3 feet. 

$$