630
FZUS63 KMQT 011343
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
943 AM EDT Tue Oct 1 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 30.4 inch high pressure currently over the Central
Plains weakens to 30.1 inches by this evening while moving into
the Midwest. This high will keep 30.0 inch ridging over Lake
Superior until Wednesday. As this high then weakens to 30.0
inches while settling over the Ohio Valley on Wednesday, a 29.6
inch low pressure trough over Manitoba and the Dakotas moves to
northern Ontario and Minnesota. This trough then sweeps across
Lake Superior Wednesday night. In its wake, a 30.1 inch high
pressure ridge builds east through the Dakotas into the Upper
Great Lakes Thursday and Friday while simultaneously strengthening
to 30.3 inches. A 29.3 inch low pressure over the Canadian
Prairies then traverses east towards Hudson and James Bay
Saturday and Sunday, bringing 29.6 inch troughing back across
Lake Superior Saturday night into Sunday.

LSZ162-012145-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
943 AM EDT Tue Oct 1 2024 /843 AM CDT Tue Oct 1 2024/

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

.REST OF TODAY...West winds 20 to 30 knots diminishing to 15 to
25 knots in the afternoon. Waves 3 to 6 feet occasionally to
8 feet subsiding to 1 to 3 feet.
.TONIGHT...West winds 10 to 20 knots becoming southwest 15 to
25 knots after midnight, then increasing to 20 to 30 knots late.
Waves building to 4 to 7 feet occasionally to 9 feet.
.WEDNESDAY...Southwest gales to 40 knots diminishing to 20 to
30 knots late. Waves building to 7 to 10 feet occasionally to
13 feet, then subsiding to 3 to 6 feet occasionally to 8 feet.
.WEDNESDAY NIGHT...West winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. Waves subsiding to calm to 2 feet.
.THURSDAY...West winds 10 to 20 knots increasing to 15 to
25 knots by mid afternoon. Waves building to 2 to 4 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots diminishing to 5 to
15 knots after midnight. Waves 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.
.SATURDAY...South winds 15 to 25 knots becoming west 20 to
30 knots. A chance of showers. Waves building to 3 to 6 feet
occasionally to 8 feet.

$$

LSZ263-012145-
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-
943 AM EDT Tue Oct 1 2024

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

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

$$

LSZ264-012145-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
943 AM EDT Tue Oct 1 2024

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

.REST OF TODAY...Northwest winds 20 to 30 knots diminishing to
15 to 25 knots in the afternoon, then backing west late. Waves
6 to 9 feet occasionally to 11 feet subsiding to 3 to 6 feet
occasionally to 8 feet.
.TONIGHT...West winds 10 to 20 knots becoming southwest 15 to
25 knots late. Waves subsiding to 2 to 4 feet, then building to
4 to 7 feet occasionally to 9 feet.
.WEDNESDAY...Southwest gales to 35 knots diminishing to 20 to
30 knots late. Waves building to 9 to 12 feet occasionally to
15 feet, then subsiding to 6 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 2 to 4 feet.
.THURSDAY...West winds 10 to 20 knots increasing to 15 to
25 knots by mid afternoon. 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 veering northwest
after midnight. Waves subsiding to 1 to 3 feet.
.FRIDAY...West winds 10 to 20 knots. Waves 1 to 3 feet.
.SATURDAY...South winds 15 to 25 knots increasing to 20 to
30 knots. A chance of showers. Waves building to 4 to 7 feet
occasionally to 9 feet.

$$

LSZ265-012145-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
943 AM EDT Tue Oct 1 2024

.REST OF TODAY...Northwest winds 20 to 30 knots backing west
late. Waves 4 to 8 feet occasionally to 10 feet, then building to
5 to 8 feet occasionally to 10 feet.
.TONIGHT...West winds 15 to 25 knots backing southwest after
midnight. Waves subsiding to 1 to 3 feet, then building to 2 to
4 feet.
.WEDNESDAY...Southwest winds 20 to 30 knots with a few gale force
gusts to 35 knots in the afternoon, then diminishing to 20 to 30
knots late. Waves building to 4 to 7 feet occasionally to 9 feet,
then subsiding to 3 to 5 feet occasionally to 7 feet.
.WEDNESDAY NIGHT...Southwest 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 calm to 2 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots. Waves calm to
2 feet.
.FRIDAY...West winds 10 to 20 knots. Waves calm to 2 feet.
.SATURDAY...South winds 15 to 25 knots increasing to 20 to
30 knots. A chance of showers. Waves building to 3 to 5 feet
occasionally to 7 feet.

$$

LSZ266-012145-
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-
943 AM EDT Tue Oct 1 2024

.REST OF TODAY...Northwest winds to 30 knots with a few gale
force gusts to 35 knots possible diminishing to 20 to 30 knots in
the afternoon. Waves 7 to 10 feet occasionally to 13 feet
subsiding to 5 to 8 feet occasionally to 10 feet.
.TONIGHT...Northwest winds 15 to 25 knots backing southwest late.
Waves subsiding to 2 to 4 feet, then building to 3 to 6 feet
occasionally to 8 feet.
.WEDNESDAY...Southwest winds 20 to 30 knots with a few gale force
gusts to 35 knots in the afternoon. Waves building to 7 to 11
feet occasionally to 14 feet.
.WEDNESDAY NIGHT...Southwest winds 20 to 30 knots becoming
northwest 10 to 20 knots after midnight. Waves subsiding to 2 to
4 feet.
.THURSDAY...West winds 10 to 20 knots. Waves 2 to 4 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots veering northwest
after midnight. Waves building to 3 to 5 feet occasionally to
7 feet, then subsiding to 2 to 4 feet.
.FRIDAY...West winds 10 to 20 knots. Waves subsiding to 1 to
3 feet.
.SATURDAY...South winds 15 to 25 knots increasing to 20 to
30 knots. Showers likely. Waves building to 4 to 7 feet
occasionally to 9 feet.

$$

LSZ267-012145-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
943 AM EDT Tue Oct 1 2024

.REST OF TODAY...Northwest winds 20 to 30 knots. Sprinkles by
late morning. Waves 5 to 9 feet occasionally to 11 feet.
.TONIGHT...Northwest winds 15 to 25 knots becoming west 10 to
20 knots after midnight, then backing southwest late. Waves
subsiding to 2 to 4 feet.
.WEDNESDAY...Southwest winds 20 to 30 knots backing south in the
afternoon, then increasing to 30 knots with a few gale force
gusts to 40 knots possible late. Waves building to 6 to 9 feet
occasionally to 11 feet.
.WEDNESDAY NIGHT...Southwest winds 20 to 30 knots becoming west
15 to 25 knots after midnight. Waves subsiding to 2 to 4 feet.
.THURSDAY...West winds 10 to 20 knots. Waves subsiding to 1 to
3 feet, then building to 2 to 4 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots veering northwest
after midnight. Waves 1 to 3 feet.
.FRIDAY...West winds 10 to 20 knots. Waves subsiding to calm to
2 feet, then building to 1 to 3 feet.
.SATURDAY...South winds 10 to 20 knots increasing to 20 to
30 knots. Showers likely. Waves building to 3 to 6 feet
occasionally to 8 feet.

$$
LSZ261-012145-
MAFOR 0115/
Superior West...GALE WARNING IN EFFECT...12630 12620 11520 11530
11540 11550. Waves 4 to 7 feet subsiding to 3 to 6 feet this
afternoon. Waves 2 to 4 feet building to 3 to 6 feet tonight.
Waves 5 to 9 feet Wednesday morning.

Superior North Central...GALE WARNING IN EFFECT...11740 11730
11630 12620 11530 12540 11550. Waves 5 to 9 feet subsiding to 4
to 7 feet this afternoon. Waves 3 to 6 feet tonight. Waves 4 to 7
feet building to 6 to 9 feet Wednesday morning.

Superior South Central 11740 12730 11630 11620 11520 11530 11540.
Waves 5 to 8 feet this afternoon. Waves 4 to 7 feet subsiding to
2 to 4 feet tonight. Waves 2 to 4 feet building to 3 to 5 feet
Wednesday morning.

Superior East 14730 11710 11610 11520 11540. Waves 6 to 10 feet
this afternoon. Waves 5 to 8 feet subsiding to 2 to 4 feet
tonight. Waves 3 to 5 feet building to 4 to 7 feet Wednesday
morning.

$$

TAP

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

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