341
FZUS63 KMQT 181401
GLFLS
OPEN LAKE FORECAST FOR LAKE SUPERIOR
NATIONAL WEATHER SERVICE MARQUETTE MI
1001 AM EDT THU SEP 18 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 30.3 INCH HIGH OVER MANITOBA SHIFTS OVER NORTHERN ONTARIO THROUGH
FRIDAY AND STRENGTHENS TO 30.4 INCHES ON SATURDAY OVER EASTERN
ONTARIO AND WESTERN QUEBEC. THE 30.4 INCH HIGH WILL MOVE TO NEW
ENGLAND BY SUNDAY MORNING. THIS BRINGS 30.2 INCH RIDGING BACK OVER
LAKE SUPERIOR LATE TODAY AND FRIDAY, WEAKENING TO 30.1 INCHES BY THE
END OF THE DAY SATURDAY. TROUGHING THEN BEGINS TO SPREAD OVER LAKE
SUPERIOR SUNDAY INTO THE BEGINNING OF NEXT WEEK AS LOW PRESSURE
DEEPENS OVER THE CANADIAN PRAIRIE TO AROUND 29.5 INCHES.
LSZ162-182000-
LAKE SUPERIOR WEST OF A LINE FROM SAXON HARBOR WI TO GRAND
PORTAGE MN BEYOND 5NM-
1001 AM EDT THU SEP 18 2025 /901 AM CDT THU SEP 18 2025/
REST OF TODAY
NORTHEAST WINDS 20 TO 30 KNOTS BECOMING EAST
15 TO 25 KNOTS LATE. A SLIGHT CHANCE OF SHOWERS. WAVES 3 TO
6 FEET OCCASIONALLY TO 8 FEET.
TONIGHT
EAST WINDS 15 TO 25 KNOTS. A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS. WAVES SUBSIDING TO 3 TO 5 FEET OCCASIONALLY TO
7 FEET.
FRIDAY
EAST WINDS 15 TO 25 KNOTS INCREASING TO 20 TO 30 KNOTS
IN THE AFTERNOON. A SLIGHT CHANCE OF THUNDERSTORMS THROUGH EARLY
AFTERNOON. A CHANCE OF SHOWERS. WAVES BUILDING TO 5 TO 8 FEET
OCCASIONALLY TO 10 FEET.
FRIDAY NIGHT
EAST WINDS 20 TO 30 KNOTS DIMINISHING TO 10 TO
20 KNOTS AFTER MIDNIGHT. A CHANCE OF SHOWERS AND A SLIGHT CHANCE
OF THUNDERSTORMS. WAVES SUBSIDING TO 2 TO 4 FEET.
SATURDAY
EAST WINDS 10 TO 20 KNOTS. SHOWERS LIKELY AND A
SLIGHT CHANCE OF THUNDERSTORMS. WAVES SUBSIDING TO CALM TO
2 FEET.
SATURDAY NIGHT
SOUTHEAST WINDS 5 TO 15 KNOTS VEERING SOUTH
AFTER MIDNIGHT. SHOWERS LIKELY THROUGH MIDNIGHT. A CHANCE OF
THUNDERSTORMS. A CHANCE OF SHOWERS AFTER MIDNIGHT. WAVES CALM TO
2 FEET.
SUNDAY
SOUTH WINDS 5 TO 15 KNOTS BACKING NORTHEAST. A CHANCE
OF SHOWERS. WAVES CALM TO 2 FEET.
MONDAY
SOUTH WINDS 5 TO 15 KNOTS BACKING NORTH. WAVES CALM TO
2 FEET.
LSZ263-182000-
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-
1001 AM EDT THU SEP 18 2025
REST OF TODAY
NORTHEAST WINDS 10 TO 20 KNOTS INCREASING TO
15 TO 25 KNOTS LATE. A SLIGHT CHANCE OF SHOWERS. WAVES 3 TO
6 FEET OCCASIONALLY TO 8 FEET.
TONIGHT
EAST WINDS 15 TO 25 KNOTS DIMINISHING TO 10 TO
20 KNOTS AFTER MIDNIGHT. A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS. WAVES SUBSIDING TO 2 TO 4 FEET.
FRIDAY
EAST WINDS 15 TO 25 KNOTS. A SLIGHT CHANCE OF SHOWERS.
WAVES BUILDING TO 3 TO 6 FEET OCCASIONALLY TO 8 FEET.
FRIDAY NIGHT
EAST WINDS 15 TO 25 KNOTS DIMINISHING TO 10 TO
20 KNOTS AFTER MIDNIGHT. A CHANCE OF SHOWERS AND A SLIGHT CHANCE
OF THUNDERSTORMS. WAVES SUBSIDING TO 2 TO 4 FEET.
SATURDAY
SOUTHEAST WINDS 10 TO 20 KNOTS. SHOWERS LIKELY AND A
SLIGHT CHANCE OF THUNDERSTORMS. WAVES BUILDING TO 3 TO 5 FEET
OCCASIONALLY TO 7 FEET.
SATURDAY NIGHT
SOUTHEAST WINDS 5 TO 15 KNOTS VEERING SOUTH
AFTER MIDNIGHT. SHOWERS LIKELY THROUGH MIDNIGHT. A CHANCE OF
SHOWERS AFTER MIDNIGHT. WAVES SUBSIDING TO 1 TO 3 FEET.
SUNDAY
SOUTH WINDS 5 TO 15 KNOTS. A CHANCE OF SHOWERS. WAVES
SUBSIDING TO CALM TO 2 FEET.
MONDAY
SOUTHWEST WINDS 5 TO 15 KNOTS VEERING NORTH. WAVES CALM
TO 2 FEET.
LSZ264-182000-
LAKE SUPERIOR FROM UPPER ENTRANCE TO PORTAGE CANAL TO MANITOU
ISLAND MI 5NM OFF SHORE TO THE US/CANADIAN BORDER-
1001 AM EDT THU SEP 18 2025
REST OF TODAY
NORTHEAST WINDS 10 TO 20 KNOTS. WAVES 2 TO
4 FEET SUBSIDING TO 1 TO 3 FEET.
TONIGHT
NORTHEAST WINDS 5 TO 15 KNOTS BECOMING EAST 10 TO
20 KNOTS AFTER MIDNIGHT. WAVES SUBSIDING TO CALM TO 2 FEET, THEN
BUILDING TO 2 TO 4 FEET.
FRIDAY
EAST WINDS 10 TO 20 KNOTS INCREASING TO 15 TO 25 KNOTS
IN THE AFTERNOON. WAVES 2 TO 4 FEET.
FRIDAY NIGHT
EAST WINDS 10 TO 20 KNOTS BECOMING SOUTHEAST
15 TO 25 KNOTS AFTER MIDNIGHT. A SLIGHT CHANCE OF SHOWERS AFTER
MIDNIGHT. WAVES BUILDING TO 3 TO 5 FEET OCCASIONALLY TO 7 FEET.
SATURDAY
SOUTHEAST WINDS 15 TO 25 KNOTS. A CHANCE OF SHOWERS
AND A SLIGHT CHANCE OF THUNDERSTORMS. WAVES BUILDING TO 3 TO
6 FEET OCCASIONALLY TO 8 FEET.
SATURDAY NIGHT
SOUTHEAST WINDS 10 TO 20 KNOTS BECOMING SOUTH
5 TO 15 KNOTS AFTER MIDNIGHT. A CHANCE OF SHOWERS. WAVES
SUBSIDING TO 2 TO 4 FEET.
SUNDAY
SOUTH WINDS 5 TO 15 KNOTS. A CHANCE OF SHOWERS. WAVES
SUBSIDING TO CALM TO 2 FEET.
MONDAY
SOUTH WINDS 5 TO 15 KNOTS VEERING SOUTHWEST. WAVES CALM
TO 2 FEET.
LSZ265-182000-
LAKE SUPERIOR WEST OF LINE FROM MANITOU ISLAND TO MARQUETTE MI
BEYOND 5NM FROM SHORE-
1001 AM EDT THU SEP 18 2025
REST OF TODAY
NORTHEAST WINDS 10 TO 20 KNOTS. WAVES 1 TO
3 FEET SUBSIDING TO CALM TO 2 FEET.
TONIGHT
NORTHEAST WINDS 10 TO 20 KNOTS VEERING EAST AFTER
MIDNIGHT. WAVES BUILDING TO 1 TO 3 FEET.
FRIDAY
EAST WINDS 15 TO 25 KNOTS. WAVES BUILDING TO 2 TO
4 FEET.
FRIDAY NIGHT
EAST WINDS 15 TO 25 KNOTS VEERING SOUTHEAST AFTER
MIDNIGHT. A SLIGHT CHANCE OF SHOWERS AFTER MIDNIGHT. WAVES 2 TO
4 FEET.
SATURDAY
SOUTHEAST WINDS 15 TO 25 KNOTS. A CHANCE OF SHOWERS.
WAVES SUBSIDING TO 1 TO 3 FEET.
SATURDAY NIGHT
SOUTHEAST WINDS 10 TO 20 KNOTS VEERING SOUTH
AFTER MIDNIGHT. A CHANCE OF SHOWERS THROUGH MIDNIGHT. SHOWERS
LIKELY AFTER MIDNIGHT. WAVES SUBSIDING TO CALM TO 2 FEET.
SUNDAY
SOUTH WINDS 10 TO 20 KNOTS DIMINISHING TO 5 TO
15 KNOTS. A CHANCE OF SHOWERS. WAVES CALM TO 2 FEET.
MONDAY
SOUTH WINDS 5 TO 15 KNOTS. WAVES CALM TO 2 FEET.
LSZ266-182000-
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-
1001 AM EDT THU SEP 18 2025
REST OF TODAY
NORTHEAST WINDS 10 TO 20 KNOTS. WAVES 1 TO
3 FEET.
TONIGHT
NORTHEAST WINDS 10 TO 20 KNOTS VEERING EAST AFTER
MIDNIGHT. WAVES BUILDING TO 2 TO 4 FEET.
FRIDAY
EAST WINDS 10 TO 20 KNOTS INCREASING TO 15 TO 25 KNOTS
IN THE AFTERNOON. WAVES SUBSIDING TO 1 TO 3 FEET.
FRIDAY NIGHT
EAST WINDS 10 TO 20 KNOTS BECOMING SOUTHEAST
15 TO 25 KNOTS AFTER MIDNIGHT. A SLIGHT CHANCE OF SHOWERS AFTER
MIDNIGHT. WAVES BUILDING TO 3 TO 5 FEET OCCASIONALLY TO 7 FEET.
SATURDAY
SOUTHEAST WINDS 15 TO 25 KNOTS. A CHANCE OF SHOWERS.
WAVES BUILDING TO 3 TO 6 FEET OCCASIONALLY TO 8 FEET.
SATURDAY NIGHT
SOUTHEAST WINDS 10 TO 20 KNOTS VEERING SOUTH
AFTER MIDNIGHT. A CHANCE OF SHOWERS THROUGH MIDNIGHT. SHOWERS
LIKELY AFTER MIDNIGHT. WAVES SUBSIDING TO 2 TO 4 FEET.
SUNDAY
SOUTH WINDS 10 TO 20 KNOTS DIMINISHING TO 5 TO
15 KNOTS. A CHANCE OF SHOWERS. WAVES SUBSIDING TO CALM TO 2 FEET.
MONDAY
SOUTH WINDS 5 TO 15 KNOTS. A CHANCE OF SHOWERS. WAVES
CALM TO 2 FEET.
LSZ267-182000-
LAKE SUPERIOR FROM GRAND MARAIS MI TO WHITEFISH POINT MI 5NM OFF
SHORE TO THE US/CANADIAN BORDER-
1001 AM EDT THU SEP 18 2025
REST OF TODAY
NORTHEAST WINDS 10 TO 20 KNOTS BACKING NORTH IN
THE AFTERNOON. WAVES 1 TO 3 FEET SUBSIDING TO CALM TO 2 FEET.
TONIGHT
NORTHEAST WINDS 10 TO 20 KNOTS VEERING EAST AFTER
MIDNIGHT. WAVES BUILDING TO 1 TO 3 FEET.
FRIDAY
EAST WINDS 10 TO 20 KNOTS DIMINISHING TO 5 TO 15 KNOTS
IN THE AFTERNOON, THEN BACKING NORTHEAST LATE. WAVES SUBSIDING TO
CALM TO 2 FEET.
FRIDAY NIGHT
EAST WINDS 10 TO 20 KNOTS BECOMING SOUTHEAST
15 TO 25 KNOTS AFTER MIDNIGHT. WAVES BUILDING TO 2 TO 4 FEET.
SATURDAY
SOUTHEAST WINDS 15 TO 25 KNOTS. A SLIGHT CHANCE OF
SHOWERS. WAVES 2 TO 4 FEET.
SATURDAY NIGHT
SOUTHEAST WINDS 15 TO 25 KNOTS. A CHANCE OF
SHOWERS THROUGH MIDNIGHT. SHOWERS LIKELY AFTER MIDNIGHT. WAVES
2 TO 4 FEET.
SUNDAY
SOUTHEAST WINDS 10 TO 20 KNOTS VEERING SOUTH. SHOWERS
LIKELY AND A CHANCE OF THUNDERSTORMS. WAVES SUBSIDING TO CALM TO
2 FEET.
MONDAY
SOUTH WINDS 10 TO 20 KNOTS. A CHANCE OF SHOWERS. WAVES
CALM TO 2 FEET.
LSZ261-182000-
MAFOR 1815/
SUPERIOR WEST 13130 14230 11230. A CHANCE OF SHOWERS FRIDAY
MORNING. WAVES 3 TO 5 FEET.
SUPERIOR NORTH CENTRAL 12120 12110 11120 13220. WAVES 2 TO 3 FEET
THIS AFTERNOON. WAVES 1 TO 3 FEET BUILDING TO 2 TO 4 FEET
TONIGHT. WAVES 2 TO 4 FEET FRIDAY MORNING.
SUPERIOR SOUTH CENTRAL 14110 11110 11210 12220. WAVES 2 TO 4
FEET.
SUPERIOR EAST 11120 11110 11810 12120 13220. WAVES 1 TO 3 FEET.
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
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