fzus63 kmqt 170801
glfls 
expires:202604172000;;510785

open lake forecast for lake superior
national weather service marquette mi
400 am edt fri apr 17 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 low of around 29.4 inches moves across lake superior late this 
afternoon through this evening. behind it, ridging builds over the 
lake, strengthening to about 30.3 inches sunday night into monday 
morning. this ridging quickly gives way to 29.8 inch troughing 
monday night into tuesday morning as a weakening low swings from the 
hudson bay shoreline of far northern ontario into james bay. high 
pressure ridging builds back to 30.2 inches over lake superior by 
tuesday night.



lsz162-172000-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
400 am edt fri apr 17 2026 /300 am cdt fri apr 17 2026/

.early this morning...east winds 10 to 20 knots. waves 1 to
3 feet building to 2 to 4 feet. 
.today...east winds 10 to 20 knots backing northeast in the
afternoon, then becoming northwest 15 to 25 knots late. rain
showers and a chance of thunderstorms by mid afternoon. waves
subsiding to 1 to 3 feet, then building to 3 to 5 feet
occasionally to 7 feet. 
.tonight...west winds 15 to 25 knots increasing to 30 knots with
a few gale force gusts to 35 knots possible. a slight chance of
rain showers through midnight. waves subsiding to 2 to 4 feet,
then building to 3 to 6 feet occasionally to 8 feet. 
.saturday...west winds to 30 knots with a few gale force gusts to
35 knots possible diminishing to 20 to 30 knots late. waves
building to 4 to 7 feet occasionally to 9 feet. 
.saturday night...northwest winds 15 to 25 knots. waves subsiding
to 1 to 3 feet. 
.sunday...northwest winds 10 to 20 knots becoming west 5 to
15 knots by mid afternoon. waves subsiding to calm to 2 feet. 
.sunday night...northwest winds 5 to 15 knots veering north after
midnight. waves calm to 2 feet. 
.monday...south winds 10 to 20 knots becoming southwest 20 to
30 knots. waves building to 2 to 4 feet, then subsiding to 1 to
3 feet. 
.tuesday...west winds 10 to 20 knots becoming northeast 5 to
15 knots. waves subsiding to calm to 2 feet. 

$$

fzus63 kmqt 170801
glfls 
expires:202604172000;;510786

open lake forecast for lake superior
national weather service marquette mi
400 am edt fri apr 17 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 low of around 29.4 inches moves across lake superior late this 
afternoon through this evening. behind it, ridging builds over the 
lake, strengthening to about 30.3 inches sunday night into monday 
morning. this ridging quickly gives way to 29.8 inch troughing 
monday night into tuesday morning as a weakening low swings from the 
hudson bay shoreline of far northern ontario into james bay. high 
pressure ridging builds back to 30.2 inches over lake superior by 
tuesday night.



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-
400 am edt fri apr 17 2026

...gale watch in effect from late tonight through saturday
evening...

.early this morning...east winds 10 to 20 knots. patchy dense
fog. a slight chance of rain showers. waves 2 to 4 feet. 
.today...southeast winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then becoming south 15 to 25 knots
late. patchy dense fog through early afternoon. rain showers
likely and a chance of thunderstorms by mid afternoon. waves
building to 4 to 7 feet occasionally to 9 feet. 
.tonight...west winds 15 to 25 knots increasing to 20 to 30 knots
after midnight. a chance of rain showers and a slight chance of
thunderstorms through midnight. waves subsiding to 3 to 5 feet
occasionally to 7 feet, then building to 5 to 8 feet occasionally
to 10 feet. 
.saturday...west winds 20 to 30 knots increasing to gales to
35 knots late. waves building to 8 to 11 feet occasionally to
14 feet. 
.saturday night...northwest winds 20 to 30 knots diminishing to
15 to 25 knots after midnight. waves subsiding to 3 to 6 feet
occasionally to 8 feet. 
.sunday...northwest winds 10 to 20 knots becoming west 5 to
15 knots by mid afternoon. waves subsiding to calm to 2 feet. 
.sunday night...northwest winds 5 to 15 knots veering north after
midnight. waves calm to 2 feet. 
.monday...south winds 15 to 25 knots becoming southwest 20 to
30 knots. waves building to 3 to 6 feet occasionally to 8 feet. 
.tuesday...west winds 15 to 25 knots becoming east 5 to 15 knots.
waves subsiding to calm to 2 feet. 

$$