360
FZUS63 KMQT 190801
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
400 AM EDT Sun Jul 19 2026

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...

30.0 high pressure moves east as a 29.5 inch low moves into Manitoba
tonight, bringing troughing of 29.7 inches to the upper Midwest. The
low will track into Ontario and deepen to 29.4 inches Monday night
with a 29.5 inch trough over Lake Superior. The low will then push
east into Quebec and retrograde to northern Quebec for midweek.
Meanwhile a 30.1 inch ridge descends southeast over the Midwest
Tuesday through Wednesday night, moving into the Ohio River Valley
on Thursday with weak ridging of 29.9 inches extending back
northwest over Lake Superior.



LSZ162-192000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
400 AM EDT Sun Jul 19 2026 /300 AM CDT Sun Jul 19 2026/

.EARLY THIS MORNING...South winds 5 to 15 knots. Patchy smoke.
Waves calm to 2 feet.
.TODAY...Southwest winds 5 to 15 knots. Patchy smoke. A slight
chance of showers. A slight chance of thunderstorms by mid
afternoon. Waves calm to 2 feet.
.TONIGHT...Southwest winds 5 to 15 knots becoming south 10 to
20 knots after midnight, then veering southwest late. A chance of
showers and a slight chance of thunderstorms. Waves building to
1 to 3 feet.
.MONDAY...Southwest winds 15 to 25 knots increasing to 20 to
30 knots in the afternoon. A chance of showers and thunderstorms.
Waves building to 3 to 5 feet occasionally to 7 feet, then
subsiding to 2 to 4 feet.
.MONDAY NIGHT...West winds 15 to 25 knots. A slight chance of
showers and thunderstorms through midnight. Waves subsiding to
calm to 2 feet, then building to 1 to 3 feet.
.TUESDAY...Northwest winds 15 to 25 knots veering north by mid
afternoon. Waves subsiding to calm to 2 feet.
.TUESDAY NIGHT...Northwest winds 10 to 20 knots diminishing to
5 to 15 knots after midnight. Waves calm to 2 feet.
.WEDNESDAY...Southwest winds 5 to 15 knots veering west. Waves
calm to 2 feet.
.THURSDAY...Southwest winds 5 to 15 knots veering west. Waves
calm to 2 feet.

$$

LSZ263-192000-
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-
400 AM EDT Sun Jul 19 2026

...DENSE SMOKE ADVISORY IN EFFECT UNTIL 8 AM EDT MONDAY...

.EARLY THIS MORNING...South winds 5 to 15 knots. Areas of smoke.
Waves calm to 2 feet.
.TODAY...Southwest winds 5 to 15 knots. Areas of smoke. Waves
calm to 2 feet.
.TONIGHT...South winds 5 to 15 knots increasing to 10 to 20 knots
after midnight, then becoming southwest 15 to 25 knots late.
Patchy smoke through midnight. A chance of showers and
thunderstorms. Waves building to 1 to 3 feet.
.MONDAY...Southwest winds 15 to 25 knots. A chance of showers and
thunderstorms. Waves building to 3 to 6 feet occasionally to
8 feet.
.MONDAY NIGHT...West winds 15 to 25 knots. A slight chance of
thunderstorms through midnight. A chance of showers. Waves
subsiding to 2 to 4 feet.
.TUESDAY...Northwest winds 15 to 25 knots veering north by mid
afternoon. Waves 2 to 4 feet.
.TUESDAY NIGHT...Northwest winds 10 to 20 knots diminishing to
5 to 15 knots after midnight. Waves subsiding to calm to 2 feet.
.WEDNESDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots. Waves calm to 2 feet.
.THURSDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots. Waves building to 1 to 3 feet, then subsiding to calm
to 2 feet.

$$

LSZ264-192000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
400 AM EDT Sun Jul 19 2026

...DENSE SMOKE ADVISORY IN EFFECT UNTIL 8 AM EDT MONDAY...

.EARLY THIS MORNING...South winds less than 10 knots. Areas of
smoke. Waves calm to 2 feet.
.TODAY...South winds 5 to 15 knots. Areas of smoke. Waves calm to
2 feet.
.TONIGHT...South winds 5 to 15 knots veering southwest after
midnight, then becoming south 10 to 20 knots late. Patchy smoke.
A chance of showers through midnight. A chance of thunderstorms.
Showers likely after midnight. Waves building to 1 to 3 feet.
.MONDAY...Southwest winds 15 to 25 knots. A chance of showers and
thunderstorms. Waves building to 3 to 5 feet occasionally to
7 feet.
.MONDAY NIGHT...Southwest winds 15 to 25 knots veering west after
midnight. Showers likely and a slight chance of thunderstorms
through midnight, then a slight chance of showers after midnight.
Waves subsiding to 2 to 4 feet.
.TUESDAY...Northwest winds 20 to 30 knots. Waves building to 3 to
6 feet occasionally to 8 feet.
.TUESDAY NIGHT...Northwest winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. Waves subsiding to 1 to 3 feet.
.WEDNESDAY...West winds 5 to 15 knots backing southwest. Waves
subsiding to calm to 2 feet.
.THURSDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.

$$

LSZ265-192000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
400 AM EDT Sun Jul 19 2026

...DENSE SMOKE ADVISORY IN EFFECT UNTIL 8 AM EDT MONDAY...

.EARLY THIS MORNING...South winds 5 to 15 knots. Areas of smoke.
Waves calm to 2 feet.
.TODAY...South winds 5 to 15 knots increasing to 10 to 20 knots
in the afternoon, then backing southeast late. Areas of smoke.
Waves calm to 2 feet.
.TONIGHT...South winds 10 to 20 knots becoming southwest 15 to
25 knots after midnight, then backing south late. Areas of smoke.
A chance of showers and thunderstorms. Waves building to 1 to
3 feet.
.MONDAY...South winds 15 to 25 knots veering southwest in the
afternoon. A chance of showers and thunderstorms. Waves 1 to
3 feet.
.MONDAY NIGHT...Southwest winds 15 to 25 knots becoming west
20 to 30 knots after midnight. Showers likely through midnight. A
chance of thunderstorms. A slight chance of showers after
midnight. Waves building to 3 to 5 feet occasionally to 7 feet.
.TUESDAY...Northwest gales to 40 knots. Waves building to 6 to
10 feet occasionally to 13 feet.
.TUESDAY NIGHT...Northwest gales to 35 knots. Waves subsiding to
3 to 6 feet occasionally to 8 feet.
.WEDNESDAY...Northwest winds 20 to 30 knots becoming southwest
10 to 20 knots. Waves subsiding to calm to 2 feet.
.THURSDAY...West winds 10 to 20 knots backing southwest. Waves
calm to 2 feet.

$$

LSZ266-192000-
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-
400 AM EDT Sun Jul 19 2026

...DENSE SMOKE ADVISORY IN EFFECT UNTIL 8 AM EDT MONDAY...

.EARLY THIS MORNING...South winds 5 to 15 knots. Areas of smoke.
Waves calm to 2 feet.
.TODAY...South winds 5 to 15 knots. Areas of smoke. Waves calm to
2 feet.
.TONIGHT...South winds 10 to 20 knots increasing to 15 to
25 knots after midnight, then veering southwest late. Areas of
smoke. A chance of showers and thunderstorms. Waves building to
2 to 4 feet.
.MONDAY...South winds 15 to 25 knots. A chance of showers and
thunderstorms. Waves 2 to 4 feet.
.MONDAY NIGHT...Southwest winds 15 to 25 knots becoming west
20 to 30 knots after midnight. Showers through midnight. A slight
chance of thunderstorms. A chance of showers after midnight.
Waves building to 3 to 5 feet occasionally to 7 feet.
.TUESDAY...Northwest gales to 40 knots. Waves building to 7 to
10 feet occasionally to 13 feet.
.TUESDAY NIGHT...Northwest gales to 35 knots. Waves subsiding to
5 to 8 feet occasionally to 10 feet.
.WEDNESDAY...Northwest gales to 35 knots becoming west 10 to
20 knots. Waves subsiding to calm to 2 feet.
.THURSDAY...West winds 5 to 15 knots backing south. Waves calm to
2 feet.

$$

LSZ267-192000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
400 AM EDT Sun Jul 19 2026

...DENSE SMOKE ADVISORY IN EFFECT UNTIL 8 AM EDT MONDAY...

.EARLY THIS MORNING...Southwest winds 5 to 15 knots. Patchy
smoke. Waves calm to 2 feet.
.TODAY...Southwest winds 5 to 15 knots backing southeast late.
Patchy smoke through early afternoon. Waves calm to 2 feet.
.TONIGHT...South winds 5 to 15 knots increasing to 10 to 20 knots
after midnight, then becoming southwest 15 to 25 knots late.
Areas of smoke. A slight chance of showers through midnight.
Showers likely and a chance of thunderstorms after midnight.
Waves building to 2 to 4 feet.
.MONDAY...South winds 15 to 25 knots. Showers and a chance of
thunderstorms. Waves 2 to 4 feet.
.MONDAY NIGHT...South winds 15 to 25 knots becoming west 10 to
20 knots after midnight. Showers through midnight. A chance of
thunderstorms. A chance of showers after midnight. Waves
subsiding to 1 to 3 feet, then building to 2 to 4 feet.
.TUESDAY...Northwest winds 20 to 30 knots increasing to gales to
35 knots by mid afternoon. A chance of showers. Waves building to
7 to 10 feet occasionally to 13 feet.
.TUESDAY NIGHT...Northwest gales to 35 knots. Waves subsiding to
5 to 8 feet occasionally to 10 feet.
.WEDNESDAY...Northwest winds 20 to 30 knots becoming west 10 to
20 knots. Waves subsiding to calm to 2 feet.
.THURSDAY...Southwest winds 5 to 15 knots backing south. Waves
calm to 2 feet.

$$

LSZ261-191400-
MAFOR 1909/
Superior West 11400 13500 11400 11410 11320 11530. A chance of
showers and thunderstorms overnight. Waves 2 feet or less.

Superior North Central 13400 11500 11400 12410 11516. A chance of
thunderstorms overnight. Waves 2 feet or less.

Superior South Central 12400 11410 12310 12420 11520. A chance of
showers overnight. Waves 1 foot or less today. Waves 1 to 3 feet
tonight.

Superior East 12500 12400 11300 11410 11420 11520. A chance of
showers overnight. Waves 2 feet or less today. Waves 1 to 3 feet
building to 2 to 4 feet tonight.

$$

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