Expires:202505162000;;598475
FZUS63 KMQT 160801
GLFLS 

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
401 AM EDT Fri May 16 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 deep 29.0 inch low pressure spinning over the Northern 
Plains this morning is bringing troughing of around 29.3 inches 
across Lake Superior by this afternoon as it slowly trudges eastward 
with time. The center of the low arrives tonight over the southern 
lake as it weakens to 29.3 inches, before leaving into northern 
Ontario by Saturday. Behind the departing low, a 30.3 inch high 
pressure moves over northern Manitoba, extending a 30.1 inch ridge 
over the lake by Sunday morning. By early Monday, this high 
strengthens to 30.5 inches over far-northern Ontario and southern 
Hudson Bay, with the ridge over the lake building to 30.3 inches by 
Monday and remaining over Lake Superior into Tuesday.



LSZ267-162000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
401 AM EDT Fri May 16 2025

.EARLY THIS MORNING...South winds 15 to 25 knots. A chance of
showers. Waves 2 to 4 feet subsiding to 1 to 3 feet. 
.TODAY...South winds 10 to 20 knots becoming southeast 15 to
25 knots in the afternoon, then becoming south 20 to 30 knots
late. Waves subsiding to calm to 2 feet, then building to 3 to
5 feet occasionally to 7 feet. 
.TONIGHT...South winds 15 to 25 knots backing southeast after
midnight, then diminishing to 10 to 20 knots late. A chance of
rain showers through midnight. A slight chance of thunderstorms.
Rain showers likely after midnight. Waves subsiding to 1 to
3 feet. 
.SATURDAY...Southeast winds 5 to 15 knots veering west in the
afternoon, then increasing to 10 to 20 knots late. A chance of
rain showers and a slight chance of thunderstorms through early
afternoon. Waves subsiding to calm to 2 feet, then building to
2 to 4 feet. 
.SATURDAY NIGHT...North winds 15 to 25 knots. A chance of rain
showers. Waves building to 4 to 7 feet occasionally to 9 feet,
then subsiding to 3 to 6 feet occasionally to 8 feet. 
.SUNDAY...North winds 15 to 25 knots. Waves subsiding to 2 to
4 feet. 
.SUNDAY NIGHT...North winds 10 to 20 knots veering northeast
after midnight. Waves subsiding to 1 to 3 feet. 
.MONDAY...North winds 10 to 20 knots veering northeast. Waves
subsiding to calm to 2 feet, then building to 1 to 3 feet. 
.TUESDAY...North winds 10 to 20 knots becoming northeast 15 to
25 knots. Waves building to 2 to 4 feet. 

$$