National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FZUS63 KMQT 220743
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
343 AM EDT Mon Apr 22 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...29.5 inch low pressure over southern Saskatchewan
will move east and be north of Thunder Bay Ontario by this
evening while deepening to 29.4 inches. This low develops into a
trough of 29.5 inches over eastern Lake Superior Tuesday morning
while 30.3 inch high pressure moves into northern Manitoba and
into northern Ontario by Tuesday evening. This high strengthens to
30.4 inches and 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 29.2 inches over the
North-Central Plains on Friday.

LSZ162-221545-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
343 AM EDT Mon Apr 22 2024 /243 AM CDT Mon Apr 22 2024/

.EARLY THIS MORNING...Southwest winds 10 to 20 knots. Waves calm
to 2 feet building to 1 to 3 feet.
.TODAY...Southwest winds 10 to 20 knots backing south late. Waves
1 to 3 feet.
.TONIGHT...Southwest winds 10 to 20 knots veering west late. A
chance of rain showers and a slight chance of thunderstorms
through midnight. Waves subsiding to calm to 2 feet.
.TUESDAY...Northeast winds 20 to 30 knots diminishing to 15 to
25 knots late. A slight chance of rain showers through early
afternoon. A chance of snow showers. Waves building to 5 to
8 feet occasionally to 10 feet.
.TUESDAY NIGHT...Northeast winds 10 to 20 knots. Waves subsiding
to 2 to 4 feet.
.WEDNESDAY...East winds 10 to 20 knots. Waves subsiding to 1 to
3 feet, then building to 2 to 4 feet.
.WEDNESDAY NIGHT...East winds 5 to 15 knots. Waves subsiding to
calm to 2 feet.
.THURSDAY...East winds 10 to 20 knots becoming southeast 15 to
25 knots. Waves building to 2 to 4 feet.
.FRIDAY...East winds 15 to 25 knots increasing to 20 to 30 knots.
A chance of rain showers, then rain showers. Waves subsiding to
1 to 3 feet, then building to 2 to 4 feet.

$$

LSZ263-221545-
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-
343 AM EDT Mon Apr 22 2024

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

.EARLY THIS MORNING...Southwest winds 10 to 20 knots. Waves calm
to 2 feet building to 1 to 3 feet.
.TODAY...Southwest winds 15 to 25 knots diminishing to 10 to
20 knots late. Waves building to 2 to 4 feet, then subsiding to
1 to 3 feet.
.TONIGHT...Southwest winds 10 to 20 knots veering west late. A
chance of rain showers and a slight chance of thunderstorms.
Waves 1 to 3 feet.
.TUESDAY...North gales to 35 knots veering northeast in the
afternoon, then diminishing to 20 to 30 knots late. A chance of
rain showers through early afternoon. A chance of snow showers.
Waves building to 7 to 10 feet occasionally to 13 feet, then
subsiding to 5 to 8 feet occasionally to 10 feet.
.TUESDAY NIGHT...Northeast winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.WEDNESDAY...East winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. 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 increasing to 10 to
20 knots. Waves building to 2 to 4 feet.
.FRIDAY...Southeast winds 15 to 25 knots. Rain showers. Waves
building to 3 to 6 feet occasionally to 8 feet.

$$

LSZ264-221545-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
343 AM EDT Mon Apr 22 2024

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

.EARLY THIS MORNING...Southwest winds 10 to 20 knots. Waves calm
to 2 feet building to 1 to 3 feet.
.TODAY...Southwest winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon. Waves building to 2 to 4 feet, then
subsiding to 1 to 3 feet.
.TONIGHT...Southwest winds 10 to 20 knots veering west late. Rain
showers likely through midnight. A slight chance of
thunderstorms. A chance of rain showers after midnight. Waves
1 to 3 feet.
.TUESDAY...North gales to 35 knots veering northeast in the
afternoon, then diminishing to 20 to 30 knots late. A chance of
rain showers through early afternoon. A chance of snow showers.
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
15 to 25 knots after midnight. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.WEDNESDAY...East 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 10 to 20 knots increasing to 15 to
25 knots. Waves building to 3 to 6 feet occasionally to 8 feet.
.FRIDAY...Southeast winds 20 to 30 knots. A chance of rain
showers. Waves building to 4 to 7 feet occasionally to 9 feet.

$$

LSZ265-221545-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
343 AM EDT Mon Apr 22 2024

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

.EARLY THIS MORNING...Southwest winds 10 to 20 knots. Waves calm
to 2 feet.
.TODAY...Southwest winds 10 to 20 knots. Waves building to 1 to
3 feet, then subsiding to calm to 2 feet.
.TONIGHT...South winds 10 to 20 knots veering west late. Rain
showers likely through midnight. A slight chance of
thunderstorms. A chance of rain showers after midnight. Waves
building to 1 to 3 feet, then subsiding to calm to 2 feet.
.TUESDAY...West winds 15 to 25 knots becoming north gales to
35 knots in the afternoon. A slight chance of rain showers
through early afternoon. A chance of snow showers. Waves building
to 7 to 10 feet occasionally to 13 feet.
.TUESDAY NIGHT...Northeast winds 20 to 30 knots diminishing to
15 to 25 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...Southeast winds 10 to 20 knots becoming south 20 to
30 knots. Waves building to 2 to 4 feet.
.FRIDAY...Southeast winds 20 to 30 knots. Rain showers. Waves
building to 3 to 5 feet occasionally to 7 feet.

$$

LSZ266-221545-
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-
343 AM EDT Mon Apr 22 2024

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

.EARLY THIS MORNING...Southwest winds 15 to 25 knots. Waves 1 to
3 feet building to 2 to 4 feet.
.TODAY...Southwest winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then backing south late. Waves
building to 3 to 5 feet occasionally to 7 feet, then subsiding to
1 to 3 feet.
.TONIGHT...South winds 15 to 25 knots becoming southwest 10 to
20 knots late. Rain showers likely through midnight. A slight
chance of thunderstorms. A chance of rain showers after midnight.
Waves building to 3 to 5 feet occasionally to 7 feet, then
subsiding to 1 to 3 feet.
.TUESDAY...West gales to 35 knots veering north in the afternoon.
A chance of snow showers, possibly mixed with rain. Waves
building to 7 to 11 feet occasionally to 14 feet.
.TUESDAY NIGHT...Northeast winds 20 to 30 knots. Waves subsiding
to 3 to 6 feet occasionally to 8 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...Southeast 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 increasing to 15 to
25 knots. Waves building to 3 to 6 feet occasionally to 8 feet.
.FRIDAY...Southeast winds 20 to 30 knots increasing to gales to
35 knots. A chance of rain showers. Waves building to 4 to 7 feet
occasionally to 9 feet.

$$

LSZ267-221545-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
343 AM EDT Mon Apr 22 2024

...GALE WARNING IN EFFECT FROM TUESDAY AFTERNOON THROUGH LATE
TUESDAY NIGHT...

.EARLY THIS MORNING...South winds 10 to 20 knots. Waves calm to
2 feet building to 1 to 3 feet.
.TODAY...Southwest winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then becoming south 15 to 25 knots
late. Waves building to 2 to 4 feet, then subsiding to 1 to
3 feet.
.TONIGHT...South winds 20 to 30 knots diminishing to 15 to
25 knots late. A chance of rain showers through midnight. A
slight chance of thunderstorms. Rain showers likely after
midnight. Waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to 1 to 3 feet.
.TUESDAY...Southwest winds 10 to 20 knots becoming north 20 to
30 knots in the afternoon, then becoming northeast gales to
35 knots late. A slight chance of rain showers. A slight chance
of snow showers by mid afternoon. Waves subsiding to calm to
2 feet, then building to 6 to 9 feet occasionally to 11 feet.
.TUESDAY NIGHT...Northeast gales to 35 knots diminishing to 20 to
30 knots after midnight. Waves building to 7 to 10 feet
occasionally to 13 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.
.WEDNESDAY...Northeast winds 15 to 25 knots becoming north 5 to
15 knots 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...Southeast winds 10 to 20 knots becoming south 15 to
25 knots. Waves building to 2 to 4 feet.
.FRIDAY...Southeast winds 20 to 30 knots increasing to gales to
35 knots. Rain showers likely. Waves building to 3 to 6 feet
occasionally to 8 feet.

$$

LSZ261-221545-
MAFOR 2209/
Superior West 13520 12420 12520 11510. A chance of rain showers
tonight. Waves 1 to 3 feet.

Superior North Central 14530 12420 11526 11520. Waves 2 to 4 feet
today. Waves 1 to 3 feet tonight.

Superior South Central 14510 11410 11420 11426 11520. Waves 1 to
3 feet.

Superior East 11420 11530 12520 11420 12430 11436. Waves 2 to 4
feet building to 3 to 5 feet, then subsiding to 2 to 3 feet
today. Waves 2 to 4 feet building to 3 to 5 feet tonight.

$$

07

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

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