172
FZUS63 KMQT 201951
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
351 PM EDT Mon May 20 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 system will shift through
lower Michigan tonight, followed by weak 29.9 inch ridging into
Tuesday morning over Lake Superior. A 29.4 inch low pressure
develops over the Plains Tuesday, then deepens to 29.2 inches as
it lifts northeast, eventually tracking near the Arrowhead late
Tuesday night. The low continues northeast into Ontario Wednesday
and Wednesday night as it weakens to 29.4 inches. 29.9 inch
ridging builds in Thursday across Lake Superior as the low slowly
moves east toward James Bay. This ridging shifts east as a 29.6
inch low lifts northeast through the Northern Plains Thursday
night into Friday. Weak troughing of 29.8 inches moves over Lake
Superior by Saturday.

LSZ162-210400-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
351 PM EDT Mon May 20 2024 /251 PM CDT Mon May 20 2024/

...GALE WATCH IN EFFECT FROM TUESDAY AFTERNOON THROUGH WEDNESDAY
EVENING...

.LATE THIS AFTERNOON...Northeast winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...Northeast winds 5 to 15 knots backing north after
midnight, then veering northeast late. Patchy fog through
midnight, then areas of dense fog after midnight. Waves calm to
2 feet.
.TUESDAY...Northeast winds 5 to 15 knots increasing to gales to
35 knots. A slight chance of rain showers through early
afternoon, then rain showers likely and a slight chance of
thunderstorms by mid afternoon. Waves building to 7 to 10 feet
occasionally to 13 feet.
.TUESDAY NIGHT...East gales to 40 knots. Showers and a chance of
thunderstorms. Waves building to 10 to 14 feet occasionally to 18
feet, then subsiding to 9 to 12 feet occasionally to 15 feet.
.WEDNESDAY...Southwest gales to 40 knots veering west by mid
afternoon. Showers likely through early afternoon, then a chance
of showers by mid afternoon. Waves subsiding to 7 to 10 feet
occasionally to 13 feet, then building to 10 to 14 feet
occasionally to 18 feet.
.WEDNESDAY NIGHT...West winds 20 to 30 knots diminishing to 15 to
25 knots after midnight. A chance of showers. Waves subsiding to
3 to 6 feet occasionally to 8 feet.
.THURSDAY...West winds 15 to 25 knots diminishing to 10 to
20 knots by mid afternoon. Waves subsiding to 1 to 3 feet.
.THURSDAY NIGHT...North winds 10 to 20 knots veering northeast
after midnight. Waves subsiding to calm to 2 feet.
.FRIDAY...East winds 10 to 20 knots increasing to 15 to 25 knots.
A chance of rain showers, then rain showers likely. Waves
building to 3 to 5 feet occasionally to 7 feet, then subsiding to
1 to 3 feet.
.SATURDAY...East winds 10 to 20 knots backing northeast. A chance
of showers. Waves subsiding to calm to 2 feet.

$$

LSZ263-210400-
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 PM EDT Mon May 20 2024

...GALE WATCH IN EFFECT FROM TUESDAY EVENING THROUGH LATE
WEDNESDAY NIGHT...

.LATE THIS AFTERNOON...Northeast winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...North winds 5 to 15 knots diminishing to less than
10 knots after midnight, then becoming northeast 5 to 15 knots
late. Patchy fog through midnight, then areas of dense fog after
midnight. Waves calm to 2 feet.
.TUESDAY...Northeast winds 5 to 15 knots increasing to 10 to
20 knots in the afternoon, then becoming east 20 to 30 knots
late. A chance of rain showers and a slight chance of
thunderstorms by mid afternoon. Waves building to 4 to 7 feet
occasionally to 9 feet.
.TUESDAY NIGHT...East gales to 40 knots becoming southeast 20 to
30 knots late. Showers and a chance of thunderstorms. Waves
building to 7 to 11 feet occasionally to 14 feet.
.WEDNESDAY...Southwest gales to 40 knots. A chance of showers.
Waves subsiding to 6 to 9 feet occasionally to 11 feet, then
building to 12 to 17 feet occasionally to 21 feet.
.WEDNESDAY NIGHT...West gales to 35 knots diminishing to 20 to
30 knots after midnight. A chance of rain showers. Waves
subsiding to 5 to 8 feet occasionally to 10 feet.
.THURSDAY...West winds 15 to 25 knots. Waves subsiding to 2 to
4 feet.
.THURSDAY NIGHT...Northwest winds 5 to 15 knots veering northeast
after midnight. Waves subsiding to calm to 2 feet.
.FRIDAY...East winds 10 to 20 knots. A chance of rain showers.
Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet.
.SATURDAY...Southeast winds 10 to 20 knots becoming northeast
5 to 15 knots. A chance of showers. Waves subsiding to calm to
2 feet.

$$

LSZ264-210400-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
351 PM EDT Mon May 20 2024

...GALE WATCH IN EFFECT FROM TUESDAY EVENING THROUGH LATE
WEDNESDAY NIGHT...

.LATE THIS AFTERNOON...East winds 5 to 15 knots. A slight chance
of rain showers. Waves calm to 2 feet.
.TONIGHT...Northwest winds 5 to 15 knots diminishing to less than
10 knots after midnight, then veering north late. Patchy fog
through midnight, then areas of dense fog after midnight. Waves
calm to 2 feet.
.TUESDAY...Northeast winds 5 to 15 knots becoming east 15 to
25 knots late. A chance of rain showers by mid afternoon. Waves
building to 1 to 3 feet.
.TUESDAY NIGHT...East winds 20 to 30 knots veering southeast
late. Showers and a chance of thunderstorms. Waves building to
7 to 11 feet occasionally to 14 feet.
.WEDNESDAY...South gales to 40 knots veering southwest by mid
afternoon. A chance of showers. Waves building to 12 to 17 feet
occasionally to 21 feet.
.WEDNESDAY NIGHT...West gales to 35 knots diminishing to 20 to
30 knots after midnight. A chance of rain showers. Waves
subsiding to 6 to 9 feet occasionally to 11 feet.
.THURSDAY...West winds 15 to 25 knots. Waves subsiding to 3 to
5 feet occasionally to 7 feet.
.THURSDAY NIGHT...Northwest winds 5 to 15 knots veering north
after midnight. Waves subsiding to calm to 2 feet.
.FRIDAY...East winds 10 to 20 knots veering southeast. A chance
of rain showers. Waves building to 1 to 3 feet.
.SATURDAY...Southeast winds 10 to 20 knots becoming south 5 to
15 knots. A chance of showers. Waves building to 2 to 4 feet,
then subsiding to calm to 2 feet.

$$

LSZ265-210400-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
351 PM EDT Mon May 20 2024

...GALE WATCH IN EFFECT FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY
EVENING...

.LATE THIS AFTERNOON...East winds 10 to 20 knots. A slight chance
of showers. Waves calm to 2 feet.
.TONIGHT...East winds 5 to 15 knots backing northwest after
midnight, then veering north late. Patchy fog through midnight,
then areas of dense fog after midnight. Waves calm to 2 feet.
.TUESDAY...North winds 5 to 15 knots veering east in the
afternoon, then increasing to 10 to 20 knots late. A chance of
rain showers by mid afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...East winds 15 to 25 knots becoming southeast
gales to 35 knots after midnight. Showers and a chance of
thunderstorms. Waves building to 4 to 7 feet occasionally to 9
feet.
.WEDNESDAY...South winds 20 to 30 knots veering west by mid
afternoon. A chance of showers. Waves subsiding to 3 to 6 feet
occasionally to 8 feet.
.WEDNESDAY NIGHT...West winds 20 to 30 knots diminishing to 15 to
25 knots after midnight. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.THURSDAY...West winds 20 to 30 knots diminishing to 15 to
25 knots by mid afternoon. Waves subsiding to calm to 2 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots becoming northwest
5 to 15 knots after midnight. Waves calm to 2 feet.
.FRIDAY...East winds 5 to 15 knots becoming southeast 10 to
20 knots. A chance of showers. Waves calm to 2 feet.
.SATURDAY...Southeast winds 10 to 20 knots diminishing to 5 to
15 knots. A chance of showers. Waves calm to 2 feet.

$$

LSZ266-210400-
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 PM EDT Mon May 20 2024

...GALE WATCH IN EFFECT FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY
EVENING...

.LATE THIS AFTERNOON...Southeast winds 10 to 20 knots. A slight
chance of showers. Waves calm to 2 feet.
.TONIGHT...Southeast winds 5 to 15 knots backing north after
midnight. Patchy fog through midnight, then areas of dense fog
after midnight. Waves calm to 2 feet.
.TUESDAY...North winds 5 to 15 knots veering northeast in the
afternoon, then becoming east 10 to 20 knots late. A slight
chance of rain showers by mid afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...East winds 15 to 25 knots becoming southeast
gales to 35 knots after midnight. Showers and a chance of
thunderstorms. Waves building to 6 to 9 feet occasionally to 11
feet.
.WEDNESDAY...South winds 20 to 30 knots veering southwest by mid
afternoon. A chance of showers. Waves building to 11 to 15 feet
occasionally to 19 feet.
.WEDNESDAY NIGHT...West winds 20 to 30 knots. Waves subsiding to
6 to 9 feet occasionally to 11 feet.
.THURSDAY...West winds 15 to 25 knots. Waves subsiding to 3 to
5 feet occasionally to 7 feet.
.THURSDAY NIGHT...Northwest winds 5 to 15 knots. Waves subsiding
to 1 to 3 feet.
.FRIDAY...East winds 5 to 15 knots becoming southeast 10 to
20 knots. A chance of rain showers. Waves subsiding to calm to
2 feet, then building to 1 to 3 feet.
.SATURDAY...Southeast winds 10 to 20 knots diminishing to 5 to
15 knots. A chance of showers. Waves building to 2 to 4 feet,
then subsiding to calm to 2 feet.

$$

LSZ267-210400-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
351 PM EDT Mon May 20 2024

...GALE WATCH IN EFFECT FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY
EVENING...

.LATE THIS AFTERNOON...East winds 10 to 20 knots. A chance of
showers. Waves calm to 2 feet.
.TONIGHT...East winds 5 to 15 knots backing north after midnight.
A slight chance of showers through midnight. Areas of fog. Waves
calm to 2 feet.
.TUESDAY...North winds 5 to 15 knots becoming northeast 10 to
20 knots late. A slight chance of rain showers by mid afternoon.
Waves calm to 2 feet.
.TUESDAY NIGHT...East winds 10 to 20 knots becoming southeast
15 to 25 knots after midnight, then increasing to gales to 35
knots late. A chance of showers through midnight. A chance of
thunderstorms. Showers after midnight. Waves building to 4 to 7
feet occasionally to 9 feet.
.WEDNESDAY...South winds 20 to 30 knots becoming southwest 15 to
25 knots by mid afternoon. A chance of showers. Waves subsiding
to 3 to 6 feet occasionally to 8 feet.
.WEDNESDAY NIGHT...West winds 15 to 25 knots backing southwest
after midnight. A chance of showers. Waves building to 4 to
7 feet occasionally to 9 feet.
.THURSDAY...West winds 15 to 25 knots. Waves subsiding to 3 to
5 feet occasionally to 7 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots veering northwest
after midnight. Waves subsiding to 1 to 3 feet.
.FRIDAY...North winds 10 to 20 knots veering southeast. A chance
of rain showers. Waves subsiding to calm to 2 feet.
.SATURDAY...Southeast winds 10 to 20 knots. A chance of showers.
Waves building to 1 to 3 feet, then subsiding to calm to 2 feet.

$$

LSZ261-210400-
MAFOR 2021/
Superior West 12100 11800 11804 11204 11100 11120 11140. A chance
of rain showers Tuesday afternoon. Waves 1 foot or less tonight.
Waves 2 feet or less building to 3 to 6 feet Tuesday.

Superior North Central 11300 11400 11700 11704 11804 11800 11100
11110. Waves 1 foot or less.

Superior South Central 11310 11200 11700 12804 11800 11100 11210.
Waves 1 foot or less.

Superior East 12300 11200 11800 11804 11800 12100. Waves 2 feet
or less.

$$

WFO MQT

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

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