585
FZUS63 KMQT 300747
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
347 AM EDT Mon Sep 30 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...As 30.2 inch high pressure over James Bay moves east
across Quebec today, a 29.2 inch low pressure just northwest of
Lake Winnipeg will deepen to 29.1 inches while tracking toward
Hudson Bay. An associated 29.8 inch trough will sweep across Lake
Superior during tonight. On Tuesday, deep low pressure of 28.6
inches will spin over northwestern Hudson Bay as a 30.3 inch high
pressure shifts eastward over the central Plains. As this high
then weakens to 30.0 inches while settling over the Ohio Valley on
Wednesday, a 29.7 inch low pressure trough over Manitoba and the
Dakotas will move to northern Ontario and Minnesota. This trough
will sweep across Lake Superior Wednesday night. In its wake, a
30.1 inch high pressure ridge will build east through the Dakotas
to the Upper Mississippi Valley during Thursday and Friday.

LSZ162-301600-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
347 AM EDT Mon Sep 30 2024 /247 AM CDT Mon Sep 30 2024/

.EARLY THIS MORNING...South winds 5 to 15 knots. Waves 1 to
3 feet subsiding to calm to 2 feet.
.TODAY...South winds 5 to 15 knots increasing to 10 to 20 knots
in the afternoon. Waves building to 1 to 3 feet.
.TONIGHT...West winds 15 to 25 knots becoming northwest to
30 knots with a few gale force gusts to 35 knots possible after
midnight, then diminishing to 20 to 30 knots late. A slight
chance of showers through midnight. Waves building to 3 to 6 feet
occasionally to 8 feet.
.TUESDAY...Northwest winds 20 to 30 knots backing west in the
afternoon, then diminishing to 15 to 25 knots late. Waves
building to 3 to 6 feet occasionally to 8 feet, then subsiding to
2 to 4 feet.
.TUESDAY NIGHT...West winds 15 to 25 knots backing southwest
after midnight. Waves subsiding to 1 to 3 feet, then building to
3 to 5 feet occasionally to 7 feet.
.WEDNESDAY...Southwest gales to 35 knots. Waves building to 6 to
9 feet occasionally to 11 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.
.WEDNESDAY NIGHT...West winds 15 to 25 knots becoming northwest
10 to 20 knots after midnight. Waves subsiding to calm to 2 feet.
.THURSDAY...West winds 10 to 20 knots. Waves building to 2 to
4 feet, then subsiding to calm to 2 feet.
.FRIDAY...West winds 10 to 20 knots. Waves building to 1 to
3 feet, then subsiding to calm to 2 feet.

$$

LSZ263-301600-
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-
347 AM EDT Mon Sep 30 2024

.EARLY THIS MORNING...South winds 5 to 15 knots. Waves 1 to
3 feet.
.TODAY...South winds 10 to 20 knots. Waves 1 to 3 feet.
.TONIGHT...South winds 15 to 25 knots becoming northwest to 30
knots with a few gale force gusts to 35 knots after midnight. A
slight chance of showers through midnight. Waves building to 4 to
8 feet occasionally to 10 feet.
.TUESDAY...Northwest winds 20 to 30 knots backing west late.
Waves subsiding to 3 to 6 feet occasionally to 8 feet.
.TUESDAY NIGHT...West winds 15 to 25 knots backing southwest
after midnight. Waves subsiding to 2 to 4 feet, then building to
3 to 5 feet occasionally to 7 feet.
.WEDNESDAY...Southwest gales to 35 knots. Waves building to 5 to
9 feet occasionally to 11 feet.
.WEDNESDAY NIGHT...West winds 15 to 25 knots becoming northwest
10 to 20 knots after midnight. Waves subsiding to 1 to 3 feet.
.THURSDAY...West winds 15 to 25 knots. Waves building to 2 to
4 feet, then subsiding to 1 to 3 feet.
.FRIDAY...West winds 10 to 20 knots. Waves 1 to 3 feet.

$$

LSZ264-301600-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
347 AM EDT Mon Sep 30 2024

.EARLY THIS MORNING...Southeast winds 5 to 15 knots. Waves calm
to 2 feet building to 1 to 3 feet.
.TODAY...South winds 10 to 20 knots increasing to 15 to 25 knots
late. Waves building to 3 to 6 feet occasionally to 8 feet.
.TONIGHT...South winds 15 to 25 knots becoming northwest to 30
knots with a few gale force gusts to 35 knots after midnight. A
chance of showers. Waves building to 4 to 7 feet occasionally to 9
feet, then subsiding to 3 to 6 feet occasionally to 8 feet.
.TUESDAY...Northwest winds 20 to 30 knots. Waves subsiding to
3 to 5 feet occasionally to 7 feet.
.TUESDAY NIGHT...West winds 15 to 25 knots backing southwest
after midnight. Waves subsiding to 2 to 4 feet.
.WEDNESDAY...South winds 20 to 30 knots veering southwest by mid
afternoon. Waves building to 5 to 8 feet occasionally to 10 feet.
.WEDNESDAY NIGHT...West winds 15 to 25 knots becoming northwest
10 to 20 knots after midnight. Waves subsiding to 2 to 4 feet.
.THURSDAY...West winds 15 to 25 knots becoming northwest 10 to
20 knots. Waves subsiding to 1 to 3 feet, then building to 2 to
4 feet.
.FRIDAY...West winds 10 to 20 knots. Waves 1 to 3 feet.

$$

LSZ265-301600-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
347 AM EDT Mon Sep 30 2024

.EARLY THIS MORNING...Southeast winds 5 to 15 knots. Waves calm
to 2 feet.
.TODAY...South winds 10 to 20 knots backing southeast in the
afternoon, then increasing to 15 to 25 knots late. Waves building
to 3 to 5 feet occasionally to 7 feet.
.TONIGHT...South winds 15 to 25 knots becoming west 20 to
30 knots after midnight, then becoming northwest to 30 knots with
a few gale force gusts to 35 knots possible late. A chance of
showers. Waves building to 3 to 6 feet occasionally to 8 feet,
then subsiding to 2 to 4 feet.
.TUESDAY...Northwest winds to 30 knots with a few gale force
gusts to 35 knots possible early diminishing to 20 to 30 knots.
Waves subsiding to 2 to 4 feet.
.TUESDAY NIGHT...West winds 10 to 20 knots backing southwest
after midnight. Waves subsiding to calm to 2 feet.
.WEDNESDAY...South winds 15 to 25 knots becoming southwest 20 to
30 knots by mid afternoon. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 2 to 4 feet.
.WEDNESDAY NIGHT...Southwest winds 15 to 25 knots becoming west
10 to 20 knots after midnight. Waves subsiding to calm to 2 feet.
.THURSDAY...West winds 10 to 20 knots. Waves calm to 2 feet.
.FRIDAY...West winds 10 to 20 knots. Waves calm to 2 feet.

$$

LSZ266-301600-
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-
347 AM EDT Mon Sep 30 2024

.EARLY THIS MORNING...Southeast winds 5 to 15 knots. Waves 1 to
3 feet.
.TODAY...South winds 10 to 20 knots increasing to 15 to 25 knots
late. Waves building to 3 to 6 feet occasionally to 8 feet.
.TONIGHT...South winds 15 to 25 knots increasing to 20 to
30 knots after midnight, then veering northwest to 30 knots with a
few gale force gusts to 35 knots late. A chance of showers. Waves
building to 5 to 8 feet occasionally to 10 feet, then subsiding
to 3 to 6 feet occasionally to 8 feet.
.TUESDAY...Northwest winds to 30 knots with a few gale force
gusts to 35 knots possible early diminishing to 20 to 30 knots.
Waves building to 5 to 9 feet occasionally to 11 feet.
.TUESDAY NIGHT...West winds 10 to 20 knots backing southwest
after midnight. Waves subsiding to 2 to 4 feet.
.WEDNESDAY...South winds 15 to 25 knots increasing to 20 to
30 knots by mid afternoon. Waves building to 4 to 7 feet
occasionally to 9 feet.
.WEDNESDAY NIGHT...Southwest winds 15 to 25 knots becoming west
10 to 20 knots after midnight. Waves subsiding to 2 to 4 feet.
.THURSDAY...West winds 10 to 20 knots veering northwest. Waves
subsiding to 1 to 3 feet, then building to 2 to 4 feet.
.FRIDAY...Northwest winds 10 to 20 knots backing west. Waves
subsiding to 1 to 3 feet.

$$

LSZ267-301600-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
347 AM EDT Mon Sep 30 2024

.EARLY THIS MORNING...Southeast winds 10 to 20 knots. Waves calm
to 2 feet building to 1 to 3 feet.
.TODAY...Southeast winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then increasing to 15 to 25 knots
late. Waves 1 to 3 feet.
.TONIGHT...South winds 15 to 25 knots veering northwest late. A
chance of showers after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet.
.TUESDAY...Northwest winds to 30 knots. A few gale force gusts to
35 knots possible early. A chance of showers in the morning.
Waves building to 5 to 9 feet occasionally to 11 feet.
.TUESDAY NIGHT...Northwest winds 10 to 20 knots backing southwest
after midnight. Waves subsiding to 1 to 3 feet.
.WEDNESDAY...South winds 15 to 25 knots increasing to 20 to
30 knots by mid afternoon. Waves building to 3 to 6 feet
occasionally to 8 feet.
.WEDNESDAY NIGHT...Southwest winds 20 to 30 knots becoming west
15 to 25 knots after midnight. Waves subsiding to 1 to 3 feet.
.THURSDAY...West winds 10 to 20 knots. A chance of showers. Waves
1 to 3 feet.
.FRIDAY...Northwest winds 10 to 20 knots backing west. Waves
subsiding to calm to 2 feet, then building to 1 to 3 feet.

$$

LSZ261-301600-
MAFOR 3009/
Superior West 11410 14420 11530 11640 11740. Waves 1 to 3 feet
today building to 4 to 7 feet tonight.

Superior North Central 13420 13430 11540 11740. A chance of
showers tonight. Waves 1 to 5 feet today building to 4 to 7 feet
tonight.

Superior South Central 11410 12420 12330 12430 11640. A chance of
showers overnight. Waves 1 to 4 feet today and 3 to 5 feet
tonight.

Superior East 14320 11320 13430. A chance of showers overnight.
Waves 2 to 3 feet today building to 3 to 6 feet tonight.

$$

Rolfson

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

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