fzus63 kmqt 200801
glfls 
expires:202604202000;;680573

open lake forecast for lake superior
national weather service marquette mi
400 am edt mon apr 20 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...

high pressure ridging of 30.3 inches remains over lake superior 
through this morning. a 29.1 inch low moving from northern manitoba 
to hudson bay on today swings a 29.8 inch trough across lake 
superior tonight into tuesday morning. 30.0 inch high pressure 
ridging returns over the lake by tuesday afternoon as the low 
weakens over hudson bay. a 29.2 inch low then develops over the 
northern rockies on wednesday and tracks into central manitoba at 
around 29.5 inches on friday. this sends 29.5 inch troughing over 
lake superior thursday night into friday.



lsz162-202000-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
400 am edt mon apr 20 2026 /300 am cdt mon apr 20 2026/

.early this morning...southwest winds 5 to 15 knots. waves calm
to 2 feet. 
.today...southwest winds 5 to 15 knots becoming south 10 to
20 knots in the afternoon, then increasing to 15 to 25 knots
late. waves building to 1 to 3 feet. 
.tonight...southwest winds 15 to 25 knots diminishing to 10 to
20 knots after midnight, then becoming northwest 5 to 15 knots
late. waves building to 2 to 4 feet, then subsiding to calm to
2 feet. 
.tuesday...west winds 5 to 15 knots backing south late. waves
calm to 2 feet. 
.tuesday night...south winds less than 10 knots becoming east
5 to 15 knots after midnight. waves calm to 2 feet. 
.wednesday...east winds 5 to 15 knots backing northeast by mid
afternoon. waves calm to 2 feet. 
.wednesday night...northeast winds 10 to 20 knots veering east
after midnight. a chance of rain showers. waves building to 2 to
4 feet. 
.thursday...east winds 10 to 20 knots increasing to 15 to
25 knots. a chance of rain showers, then rain showers likely.
waves building to 4 to 7 feet occasionally to 9 feet. 
.friday...southwest winds 15 to 25 knots veering west. waves
subsiding to calm to 2 feet. 

$$

fzus63 kmqt 200801
glfls 
expires:202604202000;;680574

open lake forecast for lake superior
national weather service marquette mi
400 am edt mon apr 20 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...

high pressure ridging of 30.3 inches remains over lake superior 
through this morning. a 29.1 inch low moving from northern manitoba 
to hudson bay on today swings a 29.8 inch trough across lake 
superior tonight into tuesday morning. 30.0 inch high pressure 
ridging returns over the lake by tuesday afternoon as the low 
weakens over hudson bay. a 29.2 inch low then develops over the 
northern rockies on wednesday and tracks into central manitoba at 
around 29.5 inches on friday. this sends 29.5 inch troughing over 
lake superior thursday night into friday.



lsz263-202000-
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 mon apr 20 2026

.early this morning...north winds 5 to 15 knots. waves calm to
2 feet. 
.today...southwest winds 5 to 15 knots becoming south 15 to
25 knots in the afternoon. waves building to 2 to 4 feet. 
.tonight...southwest winds 15 to 25 knots becoming west 10 to
20 knots late. waves building to 3 to 5 feet occasionally to
7 feet, then subsiding to 1 to 3 feet. 
.tuesday...northwest winds 5 to 15 knots backing southwest late.
waves subsiding to calm to 2 feet. 
.tuesday night...south winds less than 10 knots backing southeast
after midnight. waves calm to 2 feet. 
.wednesday...southeast winds less than 10 knots becoming east
5 to 15 knots by mid afternoon. waves calm to 2 feet. 
.wednesday night...east winds 5 to 15 knots becoming southeast
10 to 20 knots after midnight. waves building to 2 to 4 feet. 
.thursday...southeast winds 20 to 30 knots increasing to gales to
35 knots. rain showers likely. waves building to 8 to 11 feet
occasionally to 14 feet. 
.friday...west winds 20 to 30 knots diminishing to 15 to
25 knots. waves subsiding to 2 to 4 feet. 

$$