628
FZUS63 KMQT 032002
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
401 PM EDT Thu Jul 3 2025

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 weak ridge of 30.0 inches builds in across the Upper Great Lakes
today. By Friday morning, the ridging will build to 30.1 inches as
it shifts over southern Ontario and the Lower Great Lakes while a
29.3 inch low over northern Saskatchewan drapes a trough of 29.7
inches over the Northern Great Plains. By Saturday, the ridge will
shift over the East Coast and as the low moves over Hudson Bay,
pressing troughing of 29.8 inches into Lake Superior. The trough
then lingers over the lake through Sunday morning, with 30.1 inch
high pressure building over the Plains. This high moves over the
Great Lakes basin for the early portions of next week.


LSZ162-040800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
401 PM EDT Thu Jul 3 2025 /301 PM CDT Thu Jul 3 2025/

.LATE THIS AFTERNOON...Northeast winds 10 to 20 knots. Waves calm
to 2 feet building to 1 to 3 feet.
.TONIGHT...Northeast winds 10 to 20 knots diminishing to 5 to
15 knots after midnight. Scattered showers and thunderstorms
after midnight. Waves subsiding to calm to 2 feet.
.FRIDAY...East winds 10 to 20 knots. Scattered showers and
thunderstorms through early afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...Northeast winds 10 to 20 knots veering south
after midnight. Scattered showers through midnight. Scattered
thunderstorms. Showers likely after midnight. Waves calm to
2 feet.
.SATURDAY...Southwest winds 10 to 20 knots veering west by mid
afternoon. Showers and a chance of thunderstorms. Waves calm to
2 feet.
.SATURDAY NIGHT...Northwest winds 10 to 20 knots veering north
after midnight. A chance of showers through midnight. Waves calm
to 2 feet.
.SUNDAY...Northeast winds 10 to 20 knots becoming east 5 to
15 knots by mid afternoon. Waves calm to 2 feet.
.SUNDAY NIGHT...Northeast winds 5 to 15 knots backing west after
midnight. Waves calm to 2 feet.
.MONDAY...South winds 5 to 15 knots backing northeast. Waves calm
to 2 feet.
.TUESDAY...East winds 5 to 15 knots backing northeast. A chance
of showers. Waves calm to 2 feet.

$$

LSZ263-040800-
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-
401 PM EDT Thu Jul 3 2025

.LATE THIS AFTERNOON...East winds 5 to 15 knots. Waves calm to
2 feet.
.TONIGHT...East winds 5 to 15 knots becoming southeast 10 to
20 knots after midnight, then becoming south 5 to 15 knots late.
Isolated showers and thunderstorms after midnight. Waves calm to
2 feet.
.FRIDAY...South winds 5 to 15 knots. Scattered thunderstorms
through early afternoon. Scattered showers. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 10 to 20 knots. A chance of showers
and thunderstorms. Waves calm to 2 feet.
.SATURDAY...Southwest winds 5 to 15 knots veering west by mid
afternoon. Showers and a chance of thunderstorms. Waves building
to 1 to 3 feet, then subsiding to calm to 2 feet.
.SATURDAY NIGHT...West winds 5 to 15 knots veering north after
midnight. A chance of showers. Waves calm to 2 feet.
.SUNDAY...North winds 5 to 15 knots veering northeast by mid
afternoon. Waves calm to 2 feet.
.SUNDAY NIGHT...Northeast winds 5 to 15 knots becoming west less
than 10 knots after midnight. Waves calm to 2 feet.
.MONDAY...West winds 5 to 15 knots backing south. Waves calm to
2 feet.
.TUESDAY...South winds 5 to 15 knots veering west. A chance of
showers. Waves calm to 2 feet.

$$

LSZ264-040800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
401 PM EDT Thu Jul 3 2025

.LATE THIS AFTERNOON...Southeast winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...Southeast winds 5 to 15 knots increasing to 10 to
20 knots after midnight, then veering south late. Waves building
to 1 to 3 feet.
.FRIDAY...South winds 10 to 20 knots diminishing to 5 to 15 knots
in the afternoon, then backing southeast late. Isolated showers
and thunderstorms. Waves 1 to 3 feet.
.FRIDAY NIGHT...South winds 10 to 20 knots. A chance of showers
and a slight chance of thunderstorms. Waves building to 2 to
4 feet, then subsiding to 1 to 3 feet.
.SATURDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots by mid afternoon. Showers and a chance of thunderstorms.
Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...West winds 5 to 15 knots veering north after
midnight. A chance of showers. Waves building to 1 to 3 feet.
.SUNDAY...North winds 5 to 15 knots. Waves subsiding to calm to
2 feet.
.SUNDAY NIGHT...North winds 5 to 15 knots becoming west less than
10 knots after midnight. Waves calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing south. Waves calm
to 2 feet.
.TUESDAY...South winds 5 to 15 knots veering west. A chance of
showers. Waves calm to 2 feet.

$$

LSZ265-040800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
401 PM EDT Thu Jul 3 2025

.LATE THIS AFTERNOON...Southeast winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...Southeast winds 10 to 20 knots. Waves calm to 2 feet.
.FRIDAY...South winds 10 to 20 knots backing southeast in the
afternoon, then veering south late. Isolated showers and
thunderstorms. Waves building to 1 to 3 feet, then subsiding to
calm to 2 feet.
.FRIDAY NIGHT...South winds 15 to 25 knots diminishing to 10 to
20 knots late. A slight chance of showers after midnight. Waves
subsiding to calm to 2 feet.
.SATURDAY...Southwest winds 10 to 20 knots. A chance of showers
through early afternoon. A chance of thunderstorms. Showers by
mid afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...West winds 10 to 20 knots veering northwest
after midnight. Showers likely through midnight, then a chance of
showers after midnight. Waves calm to 2 feet.
.SUNDAY...North winds 10 to 20 knots. Waves calm to 2 feet.
.SUNDAY NIGHT...North winds 5 to 15 knots backing northwest after
midnight. Waves calm to 2 feet.
.MONDAY...Northeast winds 5 to 15 knots veering south. Waves calm
to 2 feet.
.TUESDAY...South winds 5 to 15 knots becoming west 10 to
20 knots. A chance of showers. Waves calm to 2 feet.

$$

LSZ266-040800-
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-
401 PM EDT Thu Jul 3 2025

.LATE THIS AFTERNOON...Southeast winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...Southeast winds 5 to 15 knots increasing to 10 to
20 knots after midnight, then veering south late. Waves building
to 1 to 3 feet.
.FRIDAY...South winds 15 to 25 knots backing southeast in the
afternoon, then veering south late. Isolated showers. Isolated
thunderstorms by mid afternoon. Waves building to 2 to 4 feet.
.FRIDAY NIGHT...South winds 15 to 25 knots. Isolated
thunderstorms through midnight. A slight chance of showers. Waves
2 to 4 feet.
.SATURDAY...South winds 10 to 20 knots veering southwest by mid
afternoon. A chance of showers through early afternoon. A chance
of thunderstorms. Showers likely by mid afternoon. Waves
subsiding to calm to 2 feet.
.SATURDAY NIGHT...West winds 10 to 20 knots veering northwest
after midnight. Showers through midnight. A chance of showers
after midnight. Waves building to 1 to 3 feet.
.SUNDAY...North winds 10 to 20 knots. Waves 1 to 3 feet.
.SUNDAY NIGHT...North winds 5 to 15 knots veering northeast after
midnight. Waves subsiding to calm to 2 feet.
.MONDAY...North winds 5 to 15 knots veering south. Waves calm to
2 feet.
.TUESDAY...South winds 5 to 15 knots becoming west 10 to
20 knots. A chance of showers. Waves calm to 2 feet.

$$

LSZ267-040800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
401 PM EDT Thu Jul 3 2025

.LATE THIS AFTERNOON...Northwest winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...Southeast winds 5 to 15 knots. Waves calm to 2 feet.
.FRIDAY...Southeast winds 10 to 20 knots veering south late.
Isolated showers and thunderstorms by mid afternoon. Waves
building to 1 to 3 feet.
.FRIDAY NIGHT...South winds 15 to 25 knots. A slight chance of
showers and thunderstorms. Waves building to 2 to 4 feet, then
subsiding to 1 to 3 feet.
.SATURDAY...South winds 10 to 20 knots veering southwest by mid
afternoon. A slight chance of showers through early afternoon,
then showers likely and a chance of thunderstorms by mid
afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...West winds 10 to 20 knots. Showers and a chance
of thunderstorms. Waves calm to 2 feet.
.SUNDAY...North winds 10 to 20 knots. Waves building to 1 to
3 feet.
.SUNDAY NIGHT...North winds 10 to 20 knots veering northeast
after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...North winds 10 to 20 knots becoming west 5 to 15 knots.
Waves calm to 2 feet.
.TUESDAY...West winds 5 to 15 knots increasing to 10 to 20 knots.
A chance of showers. Waves calm to 2 feet.

$$

LSZ261-040200-
MAFOR 0321/
Superior West 12110 12210 11210 19216 11310 19319 12310. Waves 1
to 2 feet.

Superior North Central 12310 13320 11420 19426 11420 11320. Waves
1 to 3 feet.

Superior South Central 13310 14320 11320. Waves 2 feet or less
tonight. Waves 2 to 3 feet Friday.

Superior East 11600 11400 11300 14310 11320. Waves 1 foot or less
tonight. Waves 1 to 3 feet Friday.

$$

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