679
FZUS63 KMQT 040749
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
349 AM EDT Fri Apr 4 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...30.2 inch high pressure currently over the Upper Great
Lakes builds to 30.4 inches throughout today. A weak 30.1 inch
trough will move through late tonight followed by another weak
30.1 inch through Saturday night. Troughing deepens Sunday as a
29.9 inch low organizes near Lake Michigan, then presses east into
Ontario and the lower Lakes Monday at 29.5 inches. Upstream on
Monday, 30.5 inch high will build across the Plains, resulting in
increasing pressure over Lake Superior. By Tuesday, this high
will be 30.3 inches over much of the Upper Midwest.

LSZ162-041600-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
349 AM EDT Fri Apr 4 2025 /249 AM CDT Fri Apr 4 2025/

.EARLY THIS MORNING...Southwest winds 5 to 15 knots. Waves calm
to 2 feet.
.TODAY...Southwest winds 5 to 15 knots backing southeast late.
Waves calm to 2 feet.
.TONIGHT...South winds 5 to 15 knots veering west after midnight,
then becoming northwest 15 to 25 knots late. A chance of rain
showers, possibly mixed with snow. Waves building to 2 to 4 feet.
.SATURDAY...Northwest winds 15 to 25 knots backing west late.
Waves subsiding to 1 to 3 feet.
.SATURDAY NIGHT...West winds 10 to 20 knots. Waves subsiding to
calm to 2 feet.
.SUNDAY...Northwest winds 10 to 20 knots backing west by mid
afternoon. Waves calm to 2 feet.
.SUNDAY NIGHT...North winds 15 to 25 knots. A chance of snow
showers. Waves building to 3 to 5 feet occasionally to 7 feet.
.MONDAY...North winds 15 to 25 knots diminishing to 10 to
20 knots. Waves subsiding to calm to 2 feet, then building to
1 to 3 feet.
.TUESDAY...Southwest winds 10 to 20 knots backing south. Waves
calm to 2 feet.

$$

LSZ263-041600-
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-
349 AM EDT Fri Apr 4 2025

.EARLY THIS MORNING...Southwest winds less than 10 knots. Waves
calm to 2 feet.
.TODAY...Southwest winds less than 10 knots backing south in the
afternoon, then becoming east 5 to 15 knots late. Waves calm to
2 feet.
.TONIGHT...Southeast winds 5 to 15 knots veering west after
midnight, then becoming northwest 10 to 20 knots late. A chance
of rain showers. Snow showers likely after midnight. Waves
building to 2 to 4 feet.
.SATURDAY...Northwest winds 15 to 25 knots backing west late. A
chance of snow showers through early afternoon. Waves building to
3 to 5 feet occasionally to 7 feet.
.SATURDAY NIGHT...West winds 10 to 20 knots diminishing to 5 to
15 knots after midnight. Waves subsiding to 2 to 4 feet.
.SUNDAY...Northwest winds 5 to 15 knots. Waves subsiding to calm
to 2 feet.
.SUNDAY NIGHT...North winds 15 to 25 knots. A chance of snow
showers. Waves building to 3 to 5 feet occasionally to 7 feet.
.MONDAY...North winds 15 to 25 knots diminishing to 10 to
20 knots. Waves building to 3 to 6 feet occasionally to 8 feet,
then subsiding to 1 to 3 feet.
.TUESDAY...Northwest winds 5 to 15 knots backing south. Waves
subsiding to calm to 2 feet.

$$

LSZ264-041600-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
349 AM EDT Fri Apr 4 2025

.EARLY THIS MORNING...West winds 5 to 15 knots. Waves 1 to 3 feet
subsiding to calm to 2 feet.
.TODAY...West winds less than 10 knots backing southwest in the
afternoon, then becoming south 5 to 15 knots late. Waves calm to
2 feet.
.TONIGHT...Southeast winds 5 to 15 knots veering south after
midnight, then becoming west 10 to 20 knots late. A chance of
rain showers. Snow showers after midnight. Waves calm to 2 feet.
.SATURDAY...Northwest winds 15 to 25 knots backing west late. A
chance of snow showers. Waves building to 3 to 6 feet
occasionally to 8 feet.
.SATURDAY NIGHT...Northwest winds 15 to 25 knots diminishing to
5 to 15 knots after midnight. Waves subsiding to 2 to 4 feet.
.SUNDAY...Northwest winds 5 to 15 knots. Waves subsiding to calm
to 2 feet.
.SUNDAY NIGHT...North winds 15 to 25 knots. Freezing spray after
midnight. Waves building to 3 to 6 feet occasionally to 8 feet.
.MONDAY...North winds 15 to 25 knots. Freezing spray. Waves
building to 4 to 7 feet occasionally to 9 feet, then subsiding to
3 to 5 feet occasionally to 7 feet.
.TUESDAY...Northwest winds 10 to 20 knots becoming southwest 5 to
15 knots. Waves subsiding to calm to 2 feet, then building to
1 to 3 feet.

$$

LSZ265-041600-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
349 AM EDT Fri Apr 4 2025

.EARLY THIS MORNING...West winds 5 to 15 knots. Waves calm to
2 feet.
.TODAY...Southwest winds 5 to 15 knots backing southeast in the
afternoon, then increasing to 10 to 20 knots late. Waves calm to
2 feet.
.TONIGHT...Southeast winds 10 to 20 knots becoming south 5 to
15 knots after midnight, then veering west late. A chance of rain
showers, possibly mixed with snow after midnight. Waves calm to
2 feet.
.SATURDAY...Northwest winds 15 to 25 knots increasing to 20 to
30 knots in the afternoon, then becoming west to 30 knots with a
few gale force gusts to 35 knots possible late. A chance of rain
showers through early afternoon. A chance of snow showers. Waves
building to 3 to 6 feet occasionally to 8 feet.
.SATURDAY NIGHT...West winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. Waves subsiding to calm to 2 feet.
.SUNDAY...Northwest winds 10 to 20 knots. Waves calm to 2 feet.
.SUNDAY NIGHT...North winds 10 to 20 knots increasing to 20 to
30 knots after midnight. A chance of snow showers. Waves building
to 3 to 6 feet occasionally to 8 feet.
.MONDAY...North winds 20 to 30 knots. Freezing spray. Waves
building to 5 to 8 feet occasionally to 10 feet, then subsiding
to 3 to 6 feet occasionally to 8 feet.
.TUESDAY...Northwest winds 10 to 20 knots backing south. Waves
subsiding to calm to 2 feet.

$$

LSZ266-041600-
Lake Superior East of a line from Manitou Island to Marquette MI
and West of a line from Grand Marais MI to the US/Canadian Border
Beyond 5NM from shore-
349 AM EDT Fri Apr 4 2025

.EARLY THIS MORNING...West winds 5 to 15 knots. Waves 2 to 4 feet
subsiding to 1 to 3 feet.
.TODAY...Southwest winds 5 to 15 knots backing southeast late.
Waves subsiding to calm to 2 feet.
.TONIGHT...Southeast winds 10 to 20 knots becoming south 5 to
15 knots after midnight. A chance of rain showers, possibly mixed
with freezing rain and snow showers after midnight. Waves calm to
2 feet.
.SATURDAY...Northwest winds 15 to 25 knots increasing to 30 knots
with a few gale force gusts to 35 knots possible. A chance of
rain showers through early afternoon. A chance of snow showers.
Waves building to 6 to 9 feet occasionally to 11 feet.
.SATURDAY NIGHT...Northwest winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.SUNDAY...Northwest winds 10 to 20 knots. Waves subsiding to 2 to
4 feet.
.SUNDAY NIGHT...North winds 15 to 25 knots. A chance of snow
showers. Waves building to 3 to 6 feet occasionally to 8 feet.
.MONDAY...North winds 20 to 30 knots. Freezing spray. Waves
building to 7 to 10 feet occasionally to 13 feet, then subsiding
to 4 to 7 feet occasionally to 9 feet.
.TUESDAY...Northwest winds 15 to 25 knots becoming southwest
10 to 20 knots. Waves subsiding to calm to 2 feet.

$$

LSZ267-041600-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
349 AM EDT Fri Apr 4 2025

.EARLY THIS MORNING...Northwest winds 5 to 15 knots. Waves 2 to
4 feet subsiding to 1 to 3 feet.
.TODAY...Southwest winds 5 to 15 knots backing southeast late.
Waves subsiding to calm to 2 feet.
.TONIGHT...Southeast winds 10 to 20 knots becoming south 5 to
15 knots late. Waves calm to 2 feet.
.SATURDAY...West winds 10 to 20 knots becoming northwest 20 to
30 knots in the afternoon, then increasing to 30 knots with a few
gale force gusts to 35 knots possible late. A chance of rain and
snow showers, possibly mixed with freezing rain through early
afternoon. Waves building to 6 to 9 feet occasionally to 11 feet.
.SATURDAY NIGHT...Northwest winds 20 to 30 knots diminishing to
15 to 25 knots after midnight. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.SUNDAY...Northwest winds 10 to 20 knots. Waves subsiding to 2 to
4 feet.
.SUNDAY NIGHT...Northwest winds 15 to 25 knots veering north
after midnight. Waves 2 to 4 feet.
.MONDAY...North winds 20 to 30 knots. Freezing spray. Waves
building to 7 to 10 feet occasionally to 13 feet, then subsiding
to 3 to 6 feet occasionally to 8 feet.
.TUESDAY...Northwest winds 15 to 25 knots diminishing to 10 to
20 knots. Waves subsiding to calm to 2 feet.

$$

LSZ261-041600-
MAFOR 0409/
Superior West 12500 11400 13300 11600 11720. A chance of rain
showers overnight. Waves 2 feet or less.

Superior North Central 12600 11500 12400 11310 11410 11517. A
chance of rain showers overnight. Waves 1 to 3 feet today. Waves
2 feet or less tonight.

Superior South Central 12600 11400 11300 12310 12410. Waves 2
feet or less.

Superior East 11600 11500 12400 11300 12310 11410. Waves 1 to 4
feet.

$$

GS

Experimental modernized open lake forecast is available online at
weather.gov/mqt/glftable

Graphical marine forecasts are available online at:
weather.gov/greatlakes