fzus63 kmqt 170801
glfls 
expires:202510172000;;275832

open lake forecast for lake superior
national weather service marquette mi
401 am edt fri oct 17 2025

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 29.4 inch low over northern north dakota early this morning 
continues lifting into manitoba this morning, eventually deepening 
to 29.2 inches this afternoon as it crosses northeast over lake 
winnipeg before continuing northeast to hudson bay through saturday 
afternoon. as a result, a 29.6 inch trough is sent over lake 
superior this afternoon through saturday. a secondary low develops 
over the mid mississippi valley late in the day saturday and deepens 
to at least 29.2 inches on sunday as it crosses lower michigan. this 
low reaches northern quebec/hudson bay by monday morning while a 
weak 29.8 inch ridge briefly extends over lake superior. meanwhile, 
another low pressure at 29.5 inches is developing upstream over the 
northern plains, tracking east over the region monday night before 
coalescing into a compact 29.4 inch low over the upper great lakes 
tuesday morning.



lsz162-172000-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
401 am edt fri oct 17 2025 /301 am cdt fri oct 17 2025/

.early this morning...south winds 10 to 20 knots. a slight chance
of showers. waves calm to 2 feet. 
.today...south winds 10 to 20 knots becoming southwest 15 to
25 knots late. a chance of showers. waves building to 1 to
3 feet. 
.tonight...southwest winds 15 to 25 knots diminishing to 10 to
20 knots late. waves building to 2 to 4 feet, then subsiding to
1 to 3 feet. 
.saturday...west winds 10 to 20 knots. waves subsiding to calm to
2 feet. 
.saturday night...northwest winds 10 to 20 knots increasing to
15 to 25 knots after midnight. a slight chance of showers. waves
building to 1 to 3 feet. 
.sunday...northwest winds 15 to 25 knots backing west by mid
afternoon. waves subsiding to calm to 2 feet. 
.sunday night...west winds 10 to 20 knots backing southwest after
midnight. waves calm to 2 feet. 
.monday...south winds 10 to 20 knots becoming west 15 to
25 knots. a chance of showers. waves building to 2 to 4 feet,
then subsiding to 1 to 3 feet. 
.tuesday...northwest winds 20 to 30 knots diminishing to 15 to
25 knots. a chance of rain showers. waves building to 3 to 6 feet
occasionally to 8 feet, then subsiding to 1 to 3 feet. 

$$

fzus63 kmqt 170801
glfls 
expires:202510172000;;275833

open lake forecast for lake superior
national weather service marquette mi
401 am edt fri oct 17 2025

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 29.4 inch low over northern north dakota early this morning 
continues lifting into manitoba this morning, eventually deepening 
to 29.2 inches this afternoon as it crosses northeast over lake 
winnipeg before continuing northeast to hudson bay through saturday 
afternoon. as a result, a 29.6 inch trough is sent over lake 
superior this afternoon through saturday. a secondary low develops 
over the mid mississippi valley late in the day saturday and deepens 
to at least 29.2 inches on sunday as it crosses lower michigan. this 
low reaches northern quebec/hudson bay by monday morning while a 
weak 29.8 inch ridge briefly extends over lake superior. meanwhile, 
another low pressure at 29.5 inches is developing upstream over the 
northern plains, tracking east over the region monday night before 
coalescing into a compact 29.4 inch low over the upper great lakes 
tuesday morning.



lsz263-172000-
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 fri oct 17 2025

.early this morning...south winds 10 to 20 knots. a chance of
showers. waves 1 to 3 feet. 
.today...south winds 10 to 20 knots veering southwest late. a
chance of showers. waves 1 to 3 feet. 
.tonight...southwest winds 15 to 25 knots diminishing to 10 to
20 knots late. a slight chance of showers through midnight. waves
building to 3 to 5 feet occasionally to 7 feet, then subsiding to
2 to 4 feet. 
.saturday...west winds 10 to 20 knots. waves subsiding to 1 to
3 feet. 
.saturday night...northwest winds 10 to 20 knots increasing to
15 to 25 knots after midnight. a slight chance of showers. waves
subsiding to calm to 2 feet, then building to 3 to 5 feet
occasionally to 7 feet. 
.sunday...northwest winds 20 to 30 knots backing west by mid
afternoon. waves building to 3 to 6 feet occasionally to 8 feet. 
.sunday night...west winds 10 to 20 knots backing southwest after
midnight. waves subsiding to 1 to 3 feet. 
.monday...south winds 15 to 25 knots becoming west 20 to
30 knots. a chance of showers. waves building to 4 to 7 feet
occasionally to 9 feet. 
.tuesday...northwest gales to 40 knots. a chance of rain showers.
waves building to 7 to 10 feet occasionally to 13 feet, then
subsiding to 3 to 6 feet occasionally to 8 feet. 

$$