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000
FZUS63 KMQT 180744
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
344 AM EDT Thu Apr 18 2024

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 29.8 inch low pressure currently extends across Lake
Superior and Lake Huron. This low lifts northeast and phases with
another 29.8 inch low pressure over northern Ontario today. This
broad area of low pressure over northern Ontario moves into
James Bay Friday night into Saturday, deepening to 29.3 inches.
Meanwhile, a 30.4 inch high pressure ridge builds southeast into
the Northern Plains extending weak 30.0 inch ridging across
western Lake Superior. Ridging over the lake builds to 30.1 inches
on Saturday and weakens to 30.0 inches Sunday. Troughing near
29.8 inches begins to develop over the Northern Plains and pushes
into western Lake Superior on Monday.

LSZ162-181545-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
344 AM EDT Thu Apr 18 2024 /244 AM CDT Thu Apr 18 2024/

.EARLY THIS MORNING...Southwest winds 10 to 20 knots. Waves 1 to
3 feet.
.TODAY...Southwest winds 10 to 20 knots increasing to 15 to
25 knots in the afternoon. Waves building to 3 to 6 feet
occasionally to 8 feet.
.TONIGHT...West winds 15 to 25 knots increasing to 20 to 30 knots
late. Waves subsiding to 3 to 6 feet occasionally to 8 feet.
.FRIDAY...West winds 20 to 30 knots. Waves building to 5 to
8 feet occasionally to 10 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots. Waves subsiding to
3 to 5 feet occasionally to 7 feet.
.SATURDAY...Northwest winds 20 to 30 knots becoming west 15 to
25 knots by mid afternoon. Waves 3 to 5 feet occasionally to
7 feet.
.SATURDAY NIGHT...West winds 15 to 25 knots. Waves subsiding to
1 to 3 feet, then building to 2 to 4 feet.
.SUNDAY...West winds 15 to 25 knots diminishing to 10 to
20 knots. Waves subsiding to calm to 2 feet.
.MONDAY...East winds 10 to 20 knots becoming northeast 15 to
25 knots. A chance of rain showers. Waves building to 1 to
3 feet.

$$

LSZ263-181545-
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-
344 AM EDT Thu Apr 18 2024

.EARLY THIS MORNING...West winds 5 to 15 knots. Patchy fog. Waves
2 to 4 feet.
.TODAY...Southwest winds 5 to 15 knots increasing to 15 to
25 knots in the afternoon, then veering west late. Waves
subsiding to 1 to 3 feet, then building to 3 to 6 feet
occasionally to 8 feet.
.TONIGHT...West winds 15 to 25 knots. Waves subsiding to 3 to
5 feet occasionally to 7 feet, then building to 4 to 7 feet
occasionally to 9 feet.
.FRIDAY...West winds 20 to 30 knots with a few gale force gusts
to 35 knots possible. Waves building to 7 to 11 feet occasionally
to 14 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots. A slight chance of
snow showers after midnight. Waves subsiding to 4 to 7 feet
occasionally to 9 feet.
.SATURDAY...Northwest winds 15 to 25 knots becoming west 20 to
30 knots by mid afternoon. Waves subsiding to 3 to 6 feet
occasionally to 8 feet, then building to 4 to 7 feet occasionally
to 9 feet.
.SATURDAY NIGHT...West winds 15 to 25 knots. Waves subsiding to
3 to 6 feet occasionally to 8 feet.
.SUNDAY...West winds 15 to 25 knots becoming southwest 10 to
20 knots. Waves subsiding to calm to 2 feet.
.MONDAY...South winds 5 to 15 knots becoming east 10 to 20 knots.
A chance of rain showers. Waves building to 1 to 3 feet.

$$

LSZ264-181545-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
344 AM EDT Thu Apr 18 2024

.EARLY THIS MORNING...West winds 10 to 20 knots. Patchy fog.
Waves 2 to 4 feet.
.TODAY...West winds 10 to 20 knots backing southwest in the
afternoon, then increasing to 15 to 25 knots late. Patchy fog
through early afternoon. Waves subsiding to 1 to 3 feet, then
building to 3 to 5 feet occasionally to 7 feet.
.TONIGHT...West winds 10 to 20 knots increasing to 15 to 25 knots
after midnight. Waves building to 4 to 7 feet occasionally to
9 feet.
.FRIDAY...West winds 20 to 30 knots with a few gale force gusts
to 35 knots possible. Waves building to 8 to 11 feet occasionally
to 14 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots. A slight chance of
snow showers after midnight. Waves subsiding to 4 to 7 feet
occasionally to 9 feet.
.SATURDAY...Northwest winds 15 to 25 knots becoming west 20 to
30 knots by mid afternoon. Waves subsiding to 3 to 6 feet
occasionally to 8 feet, then building to 4 to 7 feet occasionally
to 9 feet.
.SATURDAY NIGHT...West 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...West winds 20 to 30 knots becoming northwest 10 to
20 knots. Waves subsiding to 1 to 3 feet.
.MONDAY...Southwest winds 5 to 15 knots becoming east 10 to
20 knots. A chance of rain showers. Waves subsiding to calm to
2 feet, then building to 1 to 3 feet.

$$

LSZ265-181545-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
344 AM EDT Thu Apr 18 2024

.EARLY THIS MORNING...West winds 15 to 25 knots. Patchy fog.
Waves 3 to 5 feet occasionally to 7 feet subsiding to 2 to
4 feet.
.TODAY...West winds 10 to 20 knots becoming southwest 5 to
15 knots in the afternoon, then backing south late. A slight
chance of rain showers by mid afternoon. Waves subsiding to calm
to 2 feet.
.TONIGHT...Southwest winds 5 to 15 knots becoming west 10 to
20 knots after midnight, then increasing to 15 to 25 knots late.
A slight chance of rain showers through midnight. Waves building
to 2 to 4 feet.
.FRIDAY...West winds 20 to 30 knots. Waves building to 4 to
7 feet occasionally to 9 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots. A slight chance of
rain and snow showers after midnight. Waves subsiding to 3 to
6 feet occasionally to 8 feet.
.SATURDAY...West winds 20 to 30 knots diminishing to 15 to
25 knots by mid afternoon. Waves subsiding to 2 to 4 feet.
.SATURDAY NIGHT...West winds 15 to 25 knots increasing to 20 to
30 knots after midnight. Waves subsiding to 1 to 3 feet, then
building to 2 to 4 feet.
.SUNDAY...West winds 20 to 30 knots becoming southwest 10 to
20 knots. Waves subsiding to calm to 2 feet.
.MONDAY...Northeast winds 10 to 20 knots veering east. A chance
of rain showers. Waves calm to 2 feet.

$$

LSZ266-181545-
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-
344 AM EDT Thu Apr 18 2024

.EARLY THIS MORNING...Northwest winds 15 to 25 knots. Patchy fog.
Waves 3 to 5 feet occasionally to 7 feet.
.TODAY...West winds 15 to 25 knots diminishing to 5 to 15 knots
in the afternoon, then becoming south 10 to 20 knots late. Patchy
fog through early afternoon. A slight chance of rain showers by
mid afternoon. Waves subsiding to 1 to 3 feet.
.TONIGHT...Southwest winds 10 to 20 knots veering west after
midnight, then increasing to 15 to 25 knots late. A chance of
rain showers. Waves building to 3 to 6 feet occasionally to
8 feet.
.FRIDAY...West winds 20 to 30 knots with a few gale force gusts
to 35 knots possible. Waves building to 8 to 11 feet occasionally
to 14 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots with a few gale force
gusts to 35 knots possible. A slight chance of rain and snow
showers after midnight. Waves subsiding to 6 to 9 feet
occasionally to 11 feet.
.SATURDAY...Northwest winds 20 to 30 knots backing west by mid
afternoon. Waves subsiding to 4 to 7 feet occasionally to 9 feet.
.SATURDAY NIGHT...West winds 20 to 30 knots. Waves subsiding to
3 to 6 feet occasionally to 8 feet.
.SUNDAY...West winds 20 to 30 knots becoming northwest 10 to
20 knots. Waves building to 4 to 7 feet occasionally to 9 feet,
then subsiding to 1 to 3 feet.
.MONDAY...Southwest winds 10 to 20 knots becoming east 15 to
25 knots. A chance of rain showers. Waves subsiding to calm to
2 feet.

$$

LSZ267-181545-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
344 AM EDT Thu Apr 18 2024

.EARLY THIS MORNING...West winds 10 to 20 knots. Patchy fog. A
slight chance of rain showers. Waves 1 to 3 feet building to 3 to
5 feet occasionally to 7 feet.
.TODAY...West winds 15 to 25 knots diminishing to 10 to 20 knots
in the afternoon, then becoming southeast 5 to 15 knots late.
Patchy fog through early afternoon. Waves subsiding to calm to
2 feet.
.TONIGHT...South winds 5 to 15 knots becoming west 10 to 20 knots
after midnight. A chance of rain showers. Waves building to 2 to
4 feet.
.FRIDAY...West winds 15 to 25 knots increasing to 30 knots with a
few gale force gusts to 35 knots possible in the afternoon. Waves
building to 7 to 10 feet occasionally to 13 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots with a few gale force
gusts to 35 knots possible. A slight chance of rain and snow
showers. Waves subsiding to 6 to 9 feet occasionally to 11 feet.
.SATURDAY...West winds 20 to 30 knots with a few gale force gusts
to 35 knots possible. Waves building to 7 to 10 feet occasionally
to 13 feet, then subsiding to 5 to 8 feet occasionally to 10
feet.
.SATURDAY NIGHT...West winds 20 to 30 knots. Waves subsiding to
3 to 6 feet occasionally to 8 feet.
.SUNDAY...West winds 20 to 30 knots diminishing to 15 to
25 knots. Waves subsiding to 1 to 3 feet.
.MONDAY...Southwest winds 10 to 20 knots backing east. A chance
of rain showers. Waves subsiding to calm to 2 feet.

$$

LSZ261-181545-
MAFOR 1809/
Superior West 11610 11510 13530 13630. Waves 2 to 4 feet building
to 3 to 6 feet today and tonight.

Superior North Central 11720 11620 11510 11520 12530 12630. Waves
2 to 4 feet today. Waves 3 to 6 feet tonight.

Superior South Central 11640 11630 11610 12400 11510 11520 11630.
A chance of rain showers this evening. Waves 3 to 5 feet
subsiding to 1 to 3 feet today. Waves 1 foot or less building to
1 to 3 feet tonight.

Superior East 11630 19634 11730 11620 11510 12400 11510 11620. A
chance of rain showers tonight. Waves 1 to 3 feet building to 3
to 5 feet, then subsiding to 1 to 4 feet today and tonight.

$$

GS

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

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