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000
FZUS63 KMQT 220148
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
948 PM EDT Sun Apr 21 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...30.3 inch high pressure currently over the Southern
Plains is extending 30.1 inch ridging across far eastern Lake
Superior this evening. This ridging continues shifting southeast
to the Atlantic coast by Tuesday evening. Meanwhile, 29.7 inch
troughing currently over Alberta tracks east-southeast across the
Canadian Prairies while deepening on Monday. By Monday night, a
29.5 inch low pressure tracks east across northern Lake Superior
before shifting east of the Great Lakes on Tuesday. A 30.4 inch
high pressure over northern Ontario quickly shifts south across
Lake Superior Tuesday night and Wednesday. Ridging shifts east of
the area Thursday ahead of a low pressure that deepens to 29.3
inches over the North-Central Plains on Friday.

LSZ162-221000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
948 PM EDT Sun Apr 21 2024 /848 PM CDT Sun Apr 21 2024/

.REST OF TONIGHT...Southwest winds 5 to 15 knots. Waves calm to
2 feet.
.MONDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon. A chance of rain showers by mid
afternoon. Waves building to 1 to 3 feet.
.MONDAY NIGHT...Southwest winds 10 to 20 knots diminishing to
5 to 15 knots after midnight, then becoming west 10 to 20 knots
late. Rain showers likely through midnight, then a chance of rain
showers and a slight chance of thunderstorms after midnight.
Waves subsiding to calm to 2 feet.
.TUESDAY...Northeast winds 20 to 30 knots. Rain showers likely
through early afternoon. A chance of snow showers. A slight
chance of rain showers by mid afternoon. Waves building to 4 to
8 feet occasionally to 10 feet.
.TUESDAY NIGHT...Northeast winds 10 to 20 knots veering east
after midnight. Waves subsiding to 2 to 4 feet.
.WEDNESDAY...East winds 10 to 20 knots. Waves subsiding to calm
to 2 feet.
.WEDNESDAY NIGHT...East winds 10 to 20 knots diminishing to 5 to
15 knots after midnight. Waves calm to 2 feet.
.THURSDAY...East winds 5 to 15 knots increasing to 15 to
25 knots. Waves building to 1 to 3 feet.
.FRIDAY...East winds 15 to 25 knots. A chance of rain showers,
then rain showers. Waves building to 2 to 4 feet.

$$

LSZ263-221000-
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-
948 PM EDT Sun Apr 21 2024

...GALE WATCH IN EFFECT FROM TUESDAY MORNING THROUGH TUESDAY
AFTERNOON...

.REST OF TONIGHT...Southwest winds 5 to 15 knots. Waves calm to
2 feet building to 1 to 3 feet.
.MONDAY...Southwest winds 10 to 20 knots. A chance of rain
showers by mid afternoon. Waves 1 to 3 feet.
.MONDAY NIGHT...Southwest winds 10 to 20 knots diminishing to
5 to 15 knots after midnight, then becoming west 15 to 25 knots
late. Rain showers likely through midnight, then a chance of rain
showers, possibly mixed with snow after midnight. Waves building
to 3 to 6 feet occasionally to 8 feet.
.TUESDAY...Northeast gales to 35 knots. A chance of snow showers,
possibly mixed with rain. Waves building to 8 to 11 feet
occasionally to 14 feet, then subsiding to 6 to 9 feet
occasionally to 11 feet.
.TUESDAY NIGHT...Northeast winds 20 to 30 knots diminishing to
10 to 20 knots after midnight. Waves subsiding to 2 to 4 feet.
.WEDNESDAY...East winds 5 to 15 knots. Waves subsiding to calm to
2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots veering south
after midnight. Waves calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots becoming southeast 10 to
20 knots. Waves building to 2 to 4 feet.
.FRIDAY...Southeast winds 15 to 25 knots backing east. A chance
of rain showers, then rain showers likely. Waves building to 3 to
6 feet occasionally to 8 feet.

$$

LSZ264-221000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
948 PM EDT Sun Apr 21 2024

...GALE WATCH IN EFFECT FROM TUESDAY MORNING THROUGH TUESDAY
AFTERNOON...

.REST OF TONIGHT...Southeast winds 5 to 15 knots veering
southwest late. Waves calm to 2 feet building to 1 to 3 feet.
.MONDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots late. A slight chance of rain showers by mid afternoon.
Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet.
.MONDAY NIGHT...Southwest winds 5 to 15 knots becoming west 15 to
25 knots late. Rain showers. A slight chance of snow showers
after midnight. Waves building to 3 to 6 feet occasionally to
8 feet.
.TUESDAY...North gales to 35 knots. A chance of rain showers
through early afternoon. A chance of snow showers. Waves building
to 9 to 12 feet occasionally to 15 feet, then subsiding to 6 to
9 feet occasionally to 11 feet.
.TUESDAY NIGHT...Northeast winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. Waves subsiding to 2 to 4 feet.
.WEDNESDAY...Northeast winds 5 to 15 knots veering south by mid
afternoon. Waves subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...South winds 5 to 15 knots. Waves calm to
2 feet.
.THURSDAY...South winds 5 to 15 knots increasing to 10 to
20 knots. Waves building to 2 to 4 feet.
.FRIDAY...Southeast winds 15 to 25 knots. A chance of rain
showers, then rain showers likely. Waves building to 4 to 7 feet
occasionally to 9 feet.

$$

LSZ265-221000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
948 PM EDT Sun Apr 21 2024

.REST OF TONIGHT...Southeast winds 5 to 15 knots veering south
after midnight, then becoming southwest 10 to 20 knots late.
Waves calm to 2 feet.
.MONDAY...Southwest winds 10 to 20 knots backing south late.
Waves calm to 2 feet.
.MONDAY NIGHT...Southwest winds 10 to 20 knots veering west late.
Rain showers. Waves calm to 2 feet.
.TUESDAY...North winds 20 to 30 knots. Rain and snow showers
likely through early afternoon, then a chance of snow showers by
mid afternoon. Waves building to 6 to 10 feet occasionally to
13 feet.
.TUESDAY NIGHT...North winds 20 to 30 knots becoming northeast
10 to 20 knots after midnight. Waves subsiding to 3 to 6 feet
occasionally to 8 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots veering east by mid
afternoon. Waves subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. Waves calm to 2 feet.
.THURSDAY...South winds 10 to 20 knots becoming southeast 15 to
25 knots. Waves building to 1 to 3 feet.
.FRIDAY...Southeast winds 15 to 25 knots increasing to 20 to
30 knots. A chance of rain showers, then rain showers likely.
Waves building to 3 to 5 feet occasionally to 7 feet.

$$

LSZ266-221000-
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-
948 PM EDT Sun Apr 21 2024

...GALE WATCH IN EFFECT FROM TUESDAY MORNING THROUGH TUESDAY
AFTERNOON...

.REST OF TONIGHT...Southeast winds 5 to 15 knots veering south
after midnight, then increasing to 10 to 20 knots late. Waves
1 to 3 feet subsiding to calm to 2 feet, then building to 2 to
4 feet.
.MONDAY...Southwest winds 10 to 20 knots backing south late.
Waves building to 3 to 5 feet occasionally to 7 feet, then
subsiding to 1 to 3 feet.
.MONDAY NIGHT...South winds 15 to 25 knots diminishing to 10 to
20 knots after midnight, then becoming southwest 15 to 25 knots
late. Rain showers. Waves building to 3 to 5 feet occasionally to
7 feet, then subsiding to 2 to 4 feet.
.TUESDAY...North gales to 35 knots. Rain and snow showers likely
through early afternoon, then a chance of snow showers by mid
afternoon. Waves building to 9 to 12 feet occasionally to
15 feet, then subsiding to 7 to 10 feet occasionally to 13 feet.
.TUESDAY NIGHT...North winds 20 to 30 knots becoming northeast
15 to 25 knots after midnight. Waves subsiding to 4 to 7 feet
occasionally to 9 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots becoming north 5 to
15 knots by mid afternoon. Waves subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...South winds 5 to 15 knots increasing to 10 to
20 knots after midnight. Waves calm to 2 feet.
.THURSDAY...South winds 10 to 20 knots. Waves building to 2 to
4 feet.
.FRIDAY...Southeast winds 15 to 25 knots increasing to 20 to
30 knots. A chance of rain showers, then rain showers likely.
Waves building to 4 to 7 feet occasionally to 9 feet.

$$

LSZ267-221000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
948 PM EDT Sun Apr 21 2024

.REST OF TONIGHT...Northwest winds 5 to 15 knots backing south
after midnight, then increasing to 10 to 20 knots late. Waves
3 to 5 feet occasionally to 7 feet subsiding to calm to 2 feet,
then building to 1 to 3 feet.
.MONDAY...Southwest winds 15 to 25 knots backing south late.
Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet.
.MONDAY NIGHT...South winds 20 to 30 knots diminishing to 10 to
20 knots. A chance of rain showers through midnight, then rain
showers likely after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 2 to 4 feet.
.TUESDAY...West winds 20 to 30 knots veering north by mid
afternoon. Rain showers, possibly mixed with snow through early
afternoon, then a chance of snow showers, possibly mixed with
rain by mid afternoon. Waves building to 7 to 10 feet
occasionally to 13 feet.
.TUESDAY NIGHT...North winds 20 to 30 knots becoming northeast
15 to 25 knots after midnight. Waves building to 8 to 11 feet
occasionally to 14 feet, then subsiding to 4 to 7 feet
occasionally to 9 feet.
.WEDNESDAY...North winds 10 to 20 knots backing northwest by mid
afternoon. Waves subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...Northwest winds 5 to 15 knots becoming south
10 to 20 knots after midnight. Waves calm to 2 feet.
.THURSDAY...South winds 10 to 20 knots. Waves building to 1 to
3 feet.
.FRIDAY...Southeast winds 15 to 25 knots increasing to 20 to
30 knots. Rain showers likely. Waves building to 3 to 6 feet
occasionally to 8 feet.

$$
LSZ261-221000-
MAFOR 2203/
Superior West 11500 11510 13520 11420 11520 11526. Waves 1 to 3
feet.

Superior North Central 11410 11420 11510 13520 11410 11520. A
chance of showers Monday evening. Waves 1 to 3 feet overnight.
Waves 2 to 4 feet Monday. Waves 1 to 3 feet Monday evening.

Superior South Central 11310 11420 11520 12510 12410 11420. A
chance of showers Monday evening. Waves 1 to 3 feet.

Superior East 11500 11410 11420 13520 11420 11430. Waves 2 to 3
feet overnight. Waves 2 to 4 feet Monday then building to 3 to 5
feet Monday evening.

$$

EK

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

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