fzus63 kmqt 180802
glfls 
expires:202605182000;;756709

open lake forecast for lake superior
national weather service marquette mi
401 am edt mon may 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... 

low pressure will weaken over the lake today with another low 
pressure following it, reaching lake superior by tuesday morning at 
29.6 inches. afterwards, a 30.2 inch high over the northern plains 
builds to 30.4 inches tuesday night into wednesday as it traverses 
eastwards into the upper great lakes. the high pressure shifts east 
on thursday while leaving lingering ridging of at least 30.1 inches 
over lake superior into friday.



lsz162-182000-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
401 am edt mon may 18 2026 /301 am cdt mon may 18 2026/

.early this morning...northeast winds 10 to 20 knots. patchy fog.
rain showers likely and a slight chance of thunderstorms. waves
3 to 6 feet occasionally to 8 feet. 
.today...northeast winds 5 to 15 knots. patchy fog. a slight
chance of rain showers. waves subsiding to 1 to 3 feet. 
.tonight...northeast winds 15 to 25 knots. patchy fog. a chance
of rain showers through midnight. a slight chance of
thunderstorms. rain showers after midnight. waves building to
4 to 7 feet occasionally to 9 feet. 
.tuesday...north winds 10 to 20 knots backing west in the
afternoon. a chance of rain showers through early afternoon.
waves subsiding to 1 to 3 feet. 
.tuesday night...northwest winds 5 to 15 knots. waves subsiding
to calm to 2 feet. 
.wednesday...southwest winds 5 to 15 knots backing south by mid
afternoon. waves calm to 2 feet. 
.wednesday night...southeast winds 5 to 15 knots veering south
after midnight. waves calm to 2 feet. 
.thursday...east winds 5 to 15 knots. waves building to 1 to
3 feet, then subsiding to calm to 2 feet. 
.friday...east winds 5 to 15 knots backing northeast. waves
building to 1 to 3 feet, then subsiding to calm to 2 feet. 

$$

fzus63 kmqt 180802
glfls 
expires:202605182000;;756710

open lake forecast for lake superior
national weather service marquette mi
401 am edt mon may 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... 

low pressure will weaken over the lake today with another low 
pressure following it, reaching lake superior by tuesday morning at 
29.6 inches. afterwards, a 30.2 inch high over the northern plains 
builds to 30.4 inches tuesday night into wednesday as it traverses 
eastwards into the upper great lakes. the high pressure shifts east 
on thursday while leaving lingering ridging of at least 30.1 inches 
over lake superior into friday.



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-
401 am edt mon may 18 2026

.early this morning...east winds 10 to 20 knots. patchy fog. rain
showers and a slight chance of thunderstorms. waves 3 to 5 feet
occasionally to 7 feet. 
.today...north winds 10 to 20 knots diminishing to 5 to 15 knots
in the afternoon, then becoming northeast 10 to 20 knots late.
patchy fog. a slight chance of rain showers. waves subsiding to
1 to 3 feet. 
.tonight...northeast winds 15 to 25 knots. patchy fog. a chance
of rain showers through midnight. a slight chance of
thunderstorms. rain showers after midnight. waves building to
5 to 8 feet occasionally to 10 feet. 
.tuesday...north winds 15 to 25 knots becoming west 10 to
20 knots in the afternoon. a chance of rain showers through early
afternoon. waves subsiding to 2 to 4 feet. 
.tuesday night...northwest winds 10 to 20 knots diminishing to
5 to 15 knots after midnight. waves subsiding to calm to 2 feet. 
.wednesday...northwest winds 5 to 15 knots backing southwest by
mid afternoon. waves building to 1 to 3 feet. 
.wednesday night...south winds 5 to 15 knots. waves subsiding to
calm to 2 feet. 
.thursday...south winds 5 to 15 knots increasing to 10 to
20 knots. waves building to 1 to 3 feet. 
.friday...east winds 5 to 15 knots. waves subsiding to calm to
2 feet, then building to 1 to 3 feet. 

$$