National Weather Service Weather Forecast Office

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

000
FZUS63 KMQT 180148
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
948 PM EDT Wed Apr 17 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 29.7 inch low pressure is currently placed over
eastern Upper Michigan this evening. This low will weaken to 29.8
inches as it lifts northeast and begins to phase with another
29.8 inch low pressure over northern Ontario. This broad area of
low pressure over northern Ontario moves into eastern 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.


LSZ162-181000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
948 PM EDT Wed Apr 17 2024 /848 PM CDT Wed Apr 17 2024/

.REST OF TONIGHT...West winds 10 to 20 knots. A slight chance of
rain showers by late evening. Waves 3 to 5 feet occasionally to
7 feet subsiding to 1 to 3 feet.
.THURSDAY...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.
.THURSDAY NIGHT...West winds 15 to 25 knots. Waves subsiding to
2 to 4 feet, then building to 3 to 5 feet occasionally to 7 feet.
.FRIDAY...West winds 20 to 30 knots increasing to gales to
35 knots by mid afternoon. A slight chance of snow showers
through early afternoon. A chance of rain showers. Waves building
to 4 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 15 to 25 knots backing west by mid
afternoon. Waves subsiding to 1 to 3 feet.
.SATURDAY NIGHT...West winds 10 to 20 knots. Waves subsiding to
calm to 2 feet, then building to 1 to 3 feet.
.SUNDAY...Southwest winds 15 to 25 knots becoming west 10 to
20 knots. Waves building to 2 to 4 feet, then subsiding to calm
to 2 feet.
.MONDAY...Southwest winds 10 to 20 knots backing east. A chance
of rain showers. Waves building to 1 to 3 feet.

$$

LSZ263-181000-
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 Wed Apr 17 2024

.REST OF TONIGHT...Northwest winds 10 to 20 knots backing west
after midnight. A chance of rain showers. Waves 5 to 8 feet
occasionally to 10 feet subsiding to 2 to 4 feet.
.THURSDAY...West winds 5 to 15 knots becoming southwest 10 to
20 knots in the afternoon, then veering west late. Waves
subsiding to 1 to 3 feet, then building to 3 to 5 feet
occasionally to 7 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots increasing to 15 to
25 knots late. Waves building to 3 to 6 feet occasionally to
8 feet.
.FRIDAY...West gales to 35 knots. A chance of rain showers,
possibly mixed with snow. Waves building to 7 to 11 feet
occasionally to 14 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots diminishing to 15 to
25 knots after midnight. Waves subsiding to 4 to 7 feet
occasionally to 9 feet.
.SATURDAY...Northwest winds 15 to 25 knots becoming west 10 to
20 knots by mid afternoon. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.SATURDAY NIGHT...West winds 10 to 20 knots. Waves subsiding to
2 to 4 feet.
.SUNDAY...West winds 15 to 25 knots becoming southwest 10 to
20 knots. Waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to 1 to 3 feet.
.MONDAY...Southwest winds 5 to 15 knots backing east. A chance of
rain showers. Waves subsiding to calm to 2 feet, then building to
1 to 3 feet.

$$

LSZ264-181000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
948 PM EDT Wed Apr 17 2024

.REST OF TONIGHT...East winds 10 to 20 knots backing northwest
after midnight, then becoming west 15 to 25 knots late. Patchy
dense fog. A chance of rain showers. Waves 5 to 8 feet
occasionally to 10 feet subsiding to 2 to 4 feet.
.THURSDAY...West winds 5 to 15 knots backing southwest in the
afternoon, then increasing to 10 to 20 knots late. Waves
subsiding to 1 to 3 feet, then building to 2 to 4 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots increasing to 15 to
25 knots late. Waves building to 3 to 6 feet occasionally to
8 feet.
.FRIDAY...West gales to 35 knots. A slight chance of rain
showers. Waves building to 8 to 11 feet occasionally to 14 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots veering northwest after
midnight. Waves subsiding to 5 to 8 feet occasionally to 10 feet.
.SATURDAY...Northwest winds 20 to 30 knots becoming west 15 to
25 knots by mid afternoon. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.SATURDAY NIGHT...West winds 10 to 20 knots. Waves building to
3 to 6 feet occasionally to 8 feet, then subsiding to 2 to
4 feet.
.SUNDAY...West winds 15 to 25 knots becoming southwest 10 to
20 knots. Waves building to 3 to 5 feet occasionally to 7 feet,
then 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.

$$

LSZ265-181000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
948 PM EDT Wed Apr 17 2024

.REST OF TONIGHT...East winds 5 to 15 knots becoming west 20 to
30 knots after midnight, then diminishing to 15 to 25 knots late.
Patchy dense fog. A chance of rain showers. Waves 3 to 6 feet
occasionally to 8 feet subsiding to 2 to 4 feet, then building to
3 to 5 feet occasionally to 7 feet.
.THURSDAY...West winds 10 to 20 knots. A slight chance of rain
showers by mid afternoon. Waves subsiding to calm to 2 feet.
.THURSDAY NIGHT...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 1 to 3 feet.
.FRIDAY...West winds 15 to 25 knots increasing to 20 to 30 knots
by mid afternoon. A slight chance of snow showers through early
afternoon. A chance of rain showers. Waves building to 3 to
6 feet occasionally to 8 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 subsiding to 2 to 4 feet.
.SATURDAY NIGHT...West winds 15 to 25 knots. Waves subsiding to
1 to 3 feet.
.SUNDAY...West winds 15 to 25 knots becoming southwest 10 to
20 knots. Waves subsiding to calm to 2 feet.
.MONDAY...West winds 10 to 20 knots backing southeast. A chance
of rain showers. Waves calm to 2 feet.

$$

LSZ266-181000-
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 Wed Apr 17 2024

.REST OF TONIGHT...East winds 15 to 25 knots becoming west 20 to
30 knots after midnight, then diminishing to 15 to 25 knots late.
Patchy fog. A chance of rain showers. Waves 5 to 8 feet
occasionally to 10 feet subsiding to 3 to 5 feet occasionally to
7 feet.
.THURSDAY...West winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon, then backing southwest late. A slight
chance of rain showers by mid afternoon. Waves subsiding to 1 to
3 feet.
.THURSDAY NIGHT...Southwest winds 5 to 15 knots becoming west
10 to 20 knots after midnight. A chance of rain showers. Waves
building to 3 to 5 feet occasionally to 7 feet.
.FRIDAY...West winds 20 to 30 knots. A slight chance of snow
showers through early afternoon. A slight chance of rain showers.
Waves building to 7 to 10 feet occasionally to 13 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots. Waves subsiding to
6 to 9 feet occasionally to 11 feet.
.SATURDAY...Northwest gales to 35 knots becoming west 15 to
25 knots by mid afternoon. Waves subsiding to 4 to 7 feet
occasionally to 9 feet.
.SATURDAY NIGHT...West winds 15 to 25 knots. Waves subsiding to
3 to 5 feet occasionally to 7 feet.
.SUNDAY...West winds 15 to 25 knots becoming southwest 10 to
20 knots. Waves subsiding to 2 to 4 feet, then building to 3 to
5 feet occasionally to 7 feet.
.MONDAY...Southwest winds 10 to 20 knots backing southeast. A
chance of rain showers. Waves building to 1 to 3 feet.

$$

LSZ267-181000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
948 PM EDT Wed Apr 17 2024

.REST OF TONIGHT...Southeast winds 20 to 30 knots diminishing to
10 to 20 knots after midnight, then becoming west 15 to 25 knots
late. Rain showers likely by late evening, then a chance of rain
showers after midnight. Patchy fog after midnight. Waves 3 to
6 feet occasionally to 8 feet subsiding to calm to 2 feet, then
building to 2 to 4 feet.
.THURSDAY...West winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then becoming southwest 5 to 15 knots
late. Waves building to 3 to 5 feet occasionally to 7 feet, then
subsiding to 1 to 3 feet.
.THURSDAY NIGHT...South winds 5 to 15 knots becoming southwest
10 to 20 knots after midnight, then veering west late. A chance
of rain showers. Waves subsiding to calm to 2 feet, then building
to 1 to 3 feet.
.FRIDAY...West winds 15 to 25 knots increasing to 20 to 30 knots
by mid afternoon. A chance of rain showers. Waves building to
5 to 8 feet occasionally to 10 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots increasing to gales to
35 knots after midnight. A chance of rain showers, possibly mixed
with snow. Waves building to 7 to 10 feet occasionally to
13 feet.
.SATURDAY...Northwest gales to 35 knots diminishing to 20 to
30 knots by mid afternoon. Waves subsiding to 5 to 8 feet
occasionally to 10 feet.
.SATURDAY 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.
.SUNDAY...West winds 15 to 25 knots diminishing to 10 to
20 knots. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 10 to 20 knots backing southeast. A
chance of rain showers. Waves calm to 2 feet.

$$
LSZ261-181000-
MAFOR 1803/
Superior West 13620 11510 13530 11620. Waves 2 to 4 feet
overnight building to 3 to 5 feet Thursday and Thursday evening.

Superior North Central 11220 19224 11720 19724 11630 12620 12530
11520. A chance of rain showers overnight. Waves 4 to 7 feet
subsiding to 3 to 5 feet overnight through Thursday and Thursday
evening.

Superior South Central 11630 12640 11630 11620 12510 11500. A
chance of rain showers late this evening and Thursday evening.
Waves 3 to 5 feet overnight subsiding to 1 to 3 feet Thursday.
Waves 1 foot or less Thursday evening.

Superior East 11336 11520 11630 19634 11630 11620 11610 11500
11400. Waves 3 to 6 feet subsiding to 1 to 3 feet overnight.
Waves 3 to 5 feet subsiding to 1 to 3 feet Thursday evening.

$$

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