131
FZUS63 KMQT 180751
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
351 AM EDT Sat May 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...While 29.9 inch ridging remains situated over the
Lower Great Lakes today, a 29.4 inch low over southern Manitoba
will push an associated 29.6 inch trough eastward to western Lake
Superior late in the afternoon. This trough will weaken to 29.9
inches while sailing across the rest of Lake Superior during
Saturday night. The parent low pressure that was over southern
Manitoba on Saturday will weaken to 29.6 inches as it moves over
far northern Ontario during Sunday. To its south, look for a 30.0
inch high pressure ridge to settle over the Upper Great Lakes. As
this ridge builds to 30.1 inches while quickly shifting to the
Mid-Atlantic Coast on Monday, a 29.8 inch trough will move out of
the Plains and over the Great Lakes Monday afternoon and evening.
On Tuesday, a 29.4 inch low pressure will track northeast to the
Upper Mississippi Valley. This low deepens to 29.3 inches,
moving over Upper Michigan and Lake Superior during the day
Wednesday.



LSZ162-181600-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
351 AM EDT Sat May 18 2024 /251 AM CDT Sat May 18 2024/

.EARLY THIS MORNING...East winds 10 to 20 knots. Scattered
showers and thunderstorms. Waves 2 to 4 feet subsiding to 1 to
3 feet.
.TODAY...East winds 10 to 20 knots increasing to 15 to 25 knots
in the afternoon, then veering west late. Scattered showers and
thunderstorms. Waves building to 2 to 4 feet.
.TONIGHT...West winds 15 to 25 knots diminishing to 10 to
20 knots after midnight, then backing southwest late. Waves
subsiding to 1 to 3 feet.
.SUNDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon. Waves subsiding to calm to 2 feet,
then building to 1 to 3 feet.
.SUNDAY NIGHT...South winds 5 to 15 knots backing east after
midnight. A chance of showers. Waves subsiding to calm to 2 feet.
.MONDAY...East winds 10 to 20 knots backing northeast by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.MONDAY NIGHT...Northeast winds 10 to 20 knots. Waves calm to
2 feet.
.TUESDAY...Northeast winds 10 to 20 knots increasing to 15 to
25 knots. A chance of showers. A chance of thunderstorms. Showers
likely. Waves building to 3 to 5 feet occasionally to 7 feet.
.WEDNESDAY...West winds 15 to 25 knots becoming northwest 10 to
20 knots. A chance of rain showers. Waves building to 3 to 6 feet
occasionally to 8 feet, then subsiding to calm to 2 feet.

$$

LSZ263-181600-
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-
351 AM EDT Sat May 18 2024

.EARLY THIS MORNING...Southeast winds 5 to 15 knots. Isolated
showers and thunderstorms. Waves 1 to 3 feet.
.TODAY...South winds 5 to 15 knots becoming southeast 10 to
20 knots in the afternoon, then veering southwest late. Isolated
rain showers through early afternoon. A chance of thunderstorms.
Rain showers likely by mid afternoon. Waves 1 to 3 feet.
.TONIGHT...West winds 10 to 20 knots becoming southwest 5 to
15 knots late. A chance of showers and thunderstorms through
midnight. Waves building to 2 to 4 feet, then subsiding to 1 to
3 feet.
.SUNDAY...Southwest winds 5 to 15 knots increasing to 10 to
20 knots in the afternoon. Waves building to 2 to 4 feet.
.SUNDAY NIGHT...Southwest winds 10 to 20 knots becoming south
5 to 15 knots after midnight. A chance of rain showers. Waves
subsiding to calm to 2 feet.
.MONDAY...East winds 5 to 15 knots backing northeast by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.MONDAY NIGHT...Northeast winds 5 to 15 knots backing north after
midnight. Waves calm to 2 feet.
.TUESDAY...Northeast winds 5 to 15 knots becoming east 15 to
25 knots. A chance of showers. A chance of thunderstorms. Showers
likely. Waves building to 3 to 6 feet occasionally to 8 feet.
.WEDNESDAY...West winds 15 to 25 knots becoming northwest 10 to
20 knots. A chance of rain showers. Waves subsiding to 1 to
3 feet.

$$

LSZ264-181600-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
351 AM EDT Sat May 18 2024

.EARLY THIS MORNING...Southeast winds 5 to 15 knots. Isolated
showers and thunderstorms. Waves 1 to 3 feet building to 2 to
4 feet.
.TODAY...Southeast winds 5 to 15 knots increasing to 10 to
20 knots in the afternoon. A chance of showers and thunderstorms.
Waves building to 3 to 5 feet occasionally to 7 feet.
.TONIGHT...Southwest winds 10 to 20 knots veering west after
midnight, then becoming southwest 5 to 15 knots late. Rain
showers likely and a chance of thunderstorms through midnight.
Waves subsiding to 2 to 4 feet.
.SUNDAY...Southwest winds 5 to 15 knots increasing to 10 to
20 knots in the afternoon. Waves 2 to 4 feet.
.SUNDAY NIGHT...Southwest winds 5 to 15 knots backing south after
midnight. A slight chance of showers after midnight. Waves
subsiding to calm to 2 feet.
.MONDAY...Southeast winds 5 to 15 knots. A chance of showers.
Waves calm to 2 feet.
.MONDAY NIGHT...East winds 5 to 15 knots backing north after
midnight. Waves calm to 2 feet.
.TUESDAY...Northeast winds 5 to 15 knots becoming east 15 to
25 knots. Showers likely and a chance of thunderstorms. Waves
building to 3 to 6 feet occasionally to 8 feet.
.WEDNESDAY...West winds 15 to 25 knots becoming northwest 10 to
20 knots. A chance of thunderstorms. A chance of rain showers.
Waves subsiding to 2 to 4 feet.

$$

LSZ265-181600-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
351 AM EDT Sat May 18 2024

.EARLY THIS MORNING...Southeast winds 5 to 15 knots. Isolated
showers and thunderstorms. Waves 1 to 3 feet.
.TODAY...Southeast winds 10 to 20 knots increasing to 15 to
25 knots in the afternoon. A chance of showers and thunderstorms
by mid afternoon. Waves building to 2 to 4 feet.
.TONIGHT...Southwest winds 10 to 20 knots veering west after
midnight. Showers likely and a chance of thunderstorms through
midnight. Waves subsiding to calm to 2 feet.
.SUNDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.SUNDAY NIGHT...South winds 5 to 15 knots. A chance of showers
after midnight. Waves calm to 2 feet.
.MONDAY...Southeast winds 10 to 20 knots. Showers likely through
early afternoon, then a chance of showers by mid afternoon. Waves
calm to 2 feet.
.MONDAY NIGHT...East winds 5 to 15 knots backing northwest after
midnight. A chance of rain showers. Waves calm to 2 feet.
.TUESDAY...East winds 5 to 15 knots increasing to 15 to 25 knots.
A chance of showers, then showers likely and a chance of
thunderstorms. Waves building to 1 to 3 feet.
.WEDNESDAY...West winds 20 to 30 knots diminishing to 15 to
25 knots. A chance of rain showers. Waves building to 2 to
4 feet, then subsiding to calm to 2 feet.

$$

LSZ266-181600-
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-
351 AM EDT Sat May 18 2024

.EARLY THIS MORNING...South winds 10 to 20 knots. Isolated
showers and thunderstorms. Waves 1 to 3 feet.
.TODAY...South winds 10 to 20 knots becoming southeast 15 to
25 knots in the afternoon, then veering south late. A slight
chance of showers and thunderstorms by mid afternoon. Waves
building to 3 to 5 feet occasionally to 7 feet.
.TONIGHT...South winds 15 to 25 knots becoming west 10 to
20 knots after midnight. Rain showers likely and a chance of
thunderstorms through midnight. Waves subsiding to 2 to 4 feet.
.SUNDAY...Southwest winds 5 to 15 knots increasing to 10 to
20 knots in the afternoon. Waves 2 to 4 feet.
.SUNDAY NIGHT...South winds 5 to 15 knots. A slight chance of
showers after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...Southeast winds 10 to 20 knots. Showers likely. Waves
calm to 2 feet.
.MONDAY NIGHT...East winds 5 to 15 knots backing north after
midnight. A chance of rain showers. Waves calm to 2 feet.
.TUESDAY...Northeast winds 10 to 20 knots becoming east 15 to
25 knots. A chance of rain showers, then rain showers likely and
a chance of thunderstorms. Waves building to 3 to 5 feet
occasionally to 7 feet.
.WEDNESDAY...West winds 20 to 30 knots diminishing to 15 to
25 knots. A chance of rain showers. Waves subsiding to 2 to
4 feet.

$$

LSZ267-181600-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
351 AM EDT Sat May 18 2024

.EARLY THIS MORNING...Southeast winds 10 to 20 knots. Waves calm
to 2 feet.
.TODAY...Southeast winds 10 to 20 knots. Waves building to 1 to
3 feet.
.TONIGHT...South winds 10 to 20 knots veering west late. Rain
showers likely and a chance of thunderstorms. Waves building to
2 to 4 feet, then subsiding to calm to 2 feet.
.SUNDAY...West winds 5 to 15 knots backing southwest in the
afternoon. Waves calm to 2 feet.
.SUNDAY NIGHT...South winds 5 to 15 knots increasing to 10 to
20 knots after midnight. Waves calm to 2 feet.
.MONDAY...Southeast winds 10 to 20 knots. A chance of showers
through early afternoon, then showers likely by mid afternoon.
Waves calm to 2 feet.
.MONDAY NIGHT...Southeast winds 10 to 20 knots. A chance of
showers. Waves calm to 2 feet.
.TUESDAY...East winds 10 to 20 knots veering southeast. A chance
of showers, then showers likely and a chance of thunderstorms.
Waves building to 2 to 4 feet.
.WEDNESDAY...South winds 15 to 25 knots veering west. A chance of
rain showers. Waves building to 3 to 5 feet occasionally to
7 feet, then subsiding to 2 to 4 feet.

$$

LSZ261-181600-
MAFOR 1809/
Superior West 11210 11210 19219 11310 19319 11420 11526 12620
11520. Waves 2 to 4 feet.

Superior North Central 13320 11330 11430 11526 11520 11620. A
chance of thunderstorms this evening. Waves 2 to 4 feet building
to 3 to 5 feet today. Waves 3 to 5 feet subsiding to 2 to 4 feet
tonight.

Superior South Central 11420 12320 12330 11426 11516 11610. A
chance of thunderstorms this evening. Waves 1 to 3 feet building
to 2 to 4 feet today. Waves 2 to 4 feet subsiding to 1 to 3 feet
tonight.

Superior East 13310 12320 11420 11426 11510. A chance of
thunderstorms tonight. Waves 1 to 3 feet today. Waves 2 to 4 feet
tonight.

$$

LC

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weather.gov/mqt/glftable

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weather.gov/greatlakes