fzus63 kmqt 180801
glfls 
expires:202609182000;;644602

open lake forecast for lake superior
national weather service marquette mi
400 am edt fri sep 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...

30.4 inch high pressure tracks across northern ontario through 
tonight, weakening to 30.3 inches as it tracks into western quebec 
saturday morning. meanwhile, 29.8 inch low pressure develops over 
the central plains, reaching western iowa by saturday morning as 
another 29.8 inch low tracks across hudson bay. saturday into 
sunday, a 30.2 inch high over the canadian prairie builds to 30.4 
inches as it moves into northwestern ontario while 29.8 to 29.9 inch 
low pressure elongates south of the great lakes. high pressure 
slowly builds to 30.5 inches as it shifts into quebec by midday 
tuesday. the high builds further to 30.6 inches wednesday.




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 fri sep 18 2026

.early this morning...east winds 5 to 15 knots. waves 1 to
3 feet. 
.today...east winds 5 to 15 knots. a slight chance of showers by
mid afternoon. waves 1 to 3 feet. 
.tonight...east winds 5 to 15 knots veering southeast after
midnight. a slight chance of showers through midnight. waves
subsiding to calm to 2 feet. 
.saturday...southeast winds 5 to 15 knots backing northeast late.
waves calm to 2 feet. 
.saturday night...northeast winds 5 to 15 knots increasing to
10 to 20 knots after midnight. waves building to 2 to 4 feet. 
.sunday...northeast winds 20 to 30 knots increasing to gales to
35 knots by mid afternoon. waves building to 4 to 7 feet
occasionally to 9 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet. 
.sunday night...east winds 20 to 30 knots diminishing to 10 to
20 knots after midnight. waves subsiding to 1 to 3 feet. 
.monday...east winds 20 to 30 knots diminishing to 15 to
25 knots. waves subsiding to calm to 2 feet. 
.tuesday...east winds 15 to 25 knots diminishing to 10 to
20 knots. waves calm to 2 feet. 

$$

fzus63 kmqt 180801
glfls 
expires:202609182000;;644601

open lake forecast for lake superior
national weather service marquette mi
400 am edt fri sep 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...

30.4 inch high pressure tracks across northern ontario through 
tonight, weakening to 30.3 inches as it tracks into western quebec 
saturday morning. meanwhile, 29.8 inch low pressure develops over 
the central plains, reaching western iowa by saturday morning as 
another 29.8 inch low tracks across hudson bay. saturday into 
sunday, a 30.2 inch high over the canadian prairie builds to 30.4 
inches as it moves into northwestern ontario while 29.8 to 29.9 inch 
low pressure elongates south of the great lakes. high pressure 
slowly builds to 30.5 inches as it shifts into quebec by midday 
tuesday. the high builds further to 30.6 inches wednesday.




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

.early this morning...northeast winds 10 to 20 knots. waves calm
to 2 feet building to 1 to 3 feet. 
.today...east winds 10 to 20 knots. a slight chance of showers by
mid afternoon. waves building to 2 to 4 feet. 
.tonight...east winds 10 to 20 knots diminishing to 5 to 15 knots
late. a slight chance of showers through midnight. waves
subsiding to calm to 2 feet, then building to 1 to 3 feet. 
.saturday...east winds 5 to 15 knots backing northeast late.
waves subsiding to calm to 2 feet. 
.saturday night...north winds 5 to 15 knots becoming northeast
10 to 20 knots after midnight. waves building to 2 to 4 feet. 
.sunday...northeast winds 20 to 30 knots becoming east gales to
35 knots by mid afternoon. waves building to 4 to 7 feet
occasionally to 9 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet. 
.sunday night...east winds 20 to 30 knots diminishing to 15 to
25 knots after midnight. waves subsiding to 1 to 3 feet. 
.monday...east winds 20 to 30 knots diminishing to 15 to
25 knots. waves building to 2 to 4 feet, then subsiding to calm
to 2 feet. 
.tuesday...east winds 15 to 25 knots diminishing to 10 to
20 knots. waves calm to 2 feet. 

$$