Marine Weather Forecast from Environment Canada

Lake Superior Mafor Forecast and Weather Conditions
From NOAA National Weather Service Weather Forecast Office

  
209   
FZUS63 KMQT 212001  
GLFLS   
  
OPEN LAKE FORECAST FOR LAKE SUPERIOR  
NATIONAL WEATHER SERVICE MARQUETTE MI  
401 PM EDT MON SEP 21 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  
  
30.4 INCH HIGH PRESSURE SPRAWLED OUT OVER ONTARIO BEGINS TO SHIFT   
EASTWARD INTO QUEBEC TONIGHT, KEEPING WINDS OUT OF THE E/NE. THE   
HIGH SLOWLY BUILDS TO 30.5 INCHES OVER QUEBEC BY MIDDAY TUESDAY,   
TRAILING A 30.4 INCH RIDGE OVER LAKE SUPERIOR WHILE MAINLY EASTERLY   
SURFACE WINDS PERSIST. THE HIGH BUILDS FURTHER TO 30.6 INCHES BY   
WEDNESDAY, REMAINING THROUGH WEDNESDAY NIGHT BEFORE WEAKENING TO   
30.4 INCHES BY THURSDAY NIGHT. MEANWHILE, WINDS GRADUALLY VEER   
THROUGH MIDWEEK, BECOMING SOUTHERLY THURSDAY. BY LATE FRIDAY, THE   
HIGH WEAKENS TO 30.3 INCHES OVER THE EASTERN GREAT LAKES BASIN AS   
29.5 INCH LOW PRESSURE DEVELOPS OVER MONTANA.  
  
LSZ162-220800-  
LAKE SUPERIOR WEST OF A LINE FROM SAXON HARBOR WI TO GRAND  
PORTAGE MN BEYOND 5NM-  
401 PM EDT MON SEP 21 2026 /301 PM CDT MON SEP 21 2026/  
   
LATE THIS AFTERNOON  
NORTHEAST WINDS 15 TO 25 KNOTS. WAVES 1 TO  
3 FEET BUILDING TO 2 TO 4 FEET, THEN SUBSIDING TO 1 TO 3 FEET.    
TONIGHT  
EAST WINDS 10 TO 20 KNOTS DIMINISHING TO 5 TO 15 KNOTS  
AFTER MIDNIGHT. WAVES SUBSIDING TO CALM TO 2 FEET.    
TUESDAY  
EAST WINDS 5 TO 15 KNOTS INCREASING TO 10 TO 20 KNOTS  
IN THE AFTERNOON, THEN BECOMING NORTHEAST 15 TO 25 KNOTS LATE.  
WAVES BUILDING TO 2 TO 4 FEET.    
TUESDAY NIGHT  
EAST WINDS 10 TO 20 KNOTS DIMINISHING TO 5 TO  
15 KNOTS AFTER MIDNIGHT, THEN VEERING SOUTHEAST LATE. WAVES  
SUBSIDING TO CALM TO 2 FEET, THEN BUILDING TO 1 TO 3 FEET.    
WEDNESDAY  
SOUTHEAST WINDS 5 TO 15 KNOTS BECOMING EAST 10 TO  
20 KNOTS BY MID AFTERNOON. WAVES CALM TO 2 FEET.    
WEDNESDAY NIGHT  
EAST WINDS 10 TO 20 KNOTS VEERING SOUTH AFTER  
MIDNIGHT. WAVES BUILDING TO 1 TO 3 FEET, THEN SUBSIDING TO CALM  
TO 2 FEET.    
THURSDAY  
SOUTH WINDS 5 TO 15 KNOTS BACKING EAST BY MID  
AFTERNOON. WAVES CALM TO 2 FEET.    
THURSDAY NIGHT  
EAST WINDS 5 TO 15 KNOTS BECOMING SOUTH LESS  
THAN 10 KNOTS AFTER MIDNIGHT. WAVES CALM TO 2 FEET.    
FRIDAY  
EAST WINDS 5 TO 15 KNOTS. WAVES CALM TO 2 FEET.    
SATURDAY  
SOUTHEAST WINDS 5 TO 15 KNOTS VEERING SOUTH. A CHANCE  
OF SHOWERS. WAVES CALM TO 2 FEET.   
  
  
  
LSZ263-220800-  
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 MON SEP 21 2026  
   
LATE THIS AFTERNOON  
EAST WINDS 15 TO 25 KNOTS. WAVES 1 TO  
3 FEET.    
TONIGHT  
EAST WINDS 10 TO 20 KNOTS DIMINISHING TO 5 TO 15 KNOTS  
AFTER MIDNIGHT. WAVES SUBSIDING TO CALM TO 2 FEET.    
TUESDAY  
EAST WINDS 5 TO 15 KNOTS INCREASING TO 10 TO 20 KNOTS  
LATE. WAVES CALM TO 2 FEET.    
TUESDAY NIGHT  
EAST WINDS 10 TO 20 KNOTS BECOMING SOUTHEAST  
5 TO 15 KNOTS AFTER MIDNIGHT. WAVES BUILDING TO 1 TO 3 FEET, THEN  
SUBSIDING TO CALM TO 2 FEET.    
WEDNESDAY  
SOUTHEAST WINDS 5 TO 15 KNOTS BACKING EAST BY MID  
AFTERNOON. WAVES CALM TO 2 FEET.    
WEDNESDAY NIGHT  
SOUTHEAST WINDS 10 TO 20 KNOTS VEERING SOUTH  
AFTER MIDNIGHT. WAVES BUILDING TO 1 TO 3 FEET, THEN SUBSIDING TO  
CALM TO 2 FEET.    
THURSDAY  
SOUTH WINDS 5 TO 15 KNOTS BACKING EAST BY MID  
AFTERNOON. WAVES CALM TO 2 FEET.    
THURSDAY NIGHT  
SOUTHEAST WINDS 5 TO 15 KNOTS VEERING SOUTH  
AFTER MIDNIGHT. WAVES CALM TO 2 FEET.    
FRIDAY  
SOUTH WINDS 5 TO 15 KNOTS BACKING SOUTHEAST. WAVES CALM  
TO 2 FEET.    
SATURDAY  
SOUTHEAST WINDS 5 TO 15 KNOTS VEERING SOUTH. WAVES  
CALM TO 2 FEET.   
  
  
  
LSZ264-220800-  
LAKE SUPERIOR FROM UPPER ENTRANCE TO PORTAGE CANAL TO MANITOU  
ISLAND MI 5NM OFF SHORE TO THE US/CANADIAN BORDER-  
401 PM EDT MON SEP 21 2026  
   
LATE THIS AFTERNOON  
EAST WINDS 5 TO 15 KNOTS. WAVES CALM TO  
2 FEET.    
TONIGHT  
EAST WINDS 5 TO 15 KNOTS DIMINISHING TO LESS THAN  
10 KNOTS LATE. WAVES CALM TO 2 FEET.    
TUESDAY  
EAST WINDS 5 TO 15 KNOTS. WAVES CALM TO 2 FEET.    
TUESDAY NIGHT  
EAST WINDS 5 TO 15 KNOTS VEERING SOUTHEAST AFTER  
MIDNIGHT. WAVES CALM TO 2 FEET.    
WEDNESDAY  
SOUTHEAST WINDS 5 TO 15 KNOTS. WAVES CALM TO 2 FEET.   
WEDNESDAY NIGHT  
SOUTHEAST WINDS 5 TO 15 KNOTS VEERING SOUTH  
AFTER MIDNIGHT. WAVES CALM TO 2 FEET.    
THURSDAY  
SOUTH WINDS 5 TO 15 KNOTS BACKING SOUTHEAST BY MID  
AFTERNOON. WAVES CALM TO 2 FEET.    
THURSDAY NIGHT  
SOUTHEAST WINDS 5 TO 15 KNOTS VEERING SOUTH  
AFTER MIDNIGHT. WAVES CALM TO 2 FEET.    
FRIDAY  
SOUTH WINDS LESS THAN 10 KNOTS BECOMING SOUTHEAST 5 TO  
15 KNOTS. WAVES CALM TO 2 FEET.    
SATURDAY  
SOUTHEAST WINDS 5 TO 15 KNOTS VEERING SOUTH. WAVES  
CALM TO 2 FEET.   
  
  
  
LSZ265-220800-  
LAKE SUPERIOR WEST OF LINE FROM MANITOU ISLAND TO MARQUETTE MI  
BEYOND 5NM FROM SHORE-  
401 PM EDT MON SEP 21 2026  
   
LATE THIS AFTERNOON  
EAST WINDS 10 TO 20 KNOTS. WAVES 1 TO  
3 FEET SUBSIDING TO CALM TO 2 FEET.    
TONIGHT  
EAST WINDS 10 TO 20 KNOTS. WAVES CALM TO 2 FEET.    
TUESDAY  
EAST WINDS 10 TO 20 KNOTS. WAVES CALM TO 2 FEET.    
TUESDAY NIGHT  
EAST WINDS 10 TO 20 KNOTS VEERING SOUTHEAST  
AFTER MIDNIGHT. WAVES CALM TO 2 FEET.    
WEDNESDAY  
SOUTHEAST WINDS 10 TO 20 KNOTS BECOMING EAST 15 TO  
25 KNOTS BY MID AFTERNOON. WAVES BUILDING TO 1 TO 3 FEET.    
WEDNESDAY NIGHT  
SOUTHEAST WINDS 15 TO 25 KNOTS BECOMING SOUTH  
10 TO 20 KNOTS AFTER MIDNIGHT. WAVES SUBSIDING TO CALM TO 2 FEET.   
THURSDAY  
SOUTH WINDS 10 TO 20 KNOTS BACKING SOUTHEAST BY MID  
AFTERNOON. WAVES CALM TO 2 FEET.    
THURSDAY NIGHT  
SOUTH WINDS 10 TO 20 KNOTS DIMINISHING TO 5 TO  
15 KNOTS AFTER MIDNIGHT. WAVES CALM TO 2 FEET.    
FRIDAY  
SOUTH WINDS 5 TO 15 KNOTS. WAVES CALM TO 2 FEET.    
SATURDAY  
SOUTHEAST WINDS 10 TO 20 KNOTS VEERING SOUTH. WAVES  
CALM TO 2 FEET.   
  
  
  
LSZ266-220800-  
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 MON SEP 21 2026  
   
LATE THIS AFTERNOON  
NORTHEAST WINDS 5 TO 15 KNOTS. WAVES 1 TO  
3 FEET SUBSIDING TO CALM TO 2 FEET.    
TONIGHT  
NORTHEAST WINDS 5 TO 15 KNOTS VEERING EAST LATE. WAVES  
CALM TO 2 FEET.    
TUESDAY  
EAST WINDS 5 TO 15 KNOTS INCREASING TO 10 TO 20 KNOTS  
LATE. WAVES CALM TO 2 FEET.    
TUESDAY NIGHT  
EAST WINDS 5 TO 15 KNOTS INCREASING TO 10 TO  
20 KNOTS AFTER MIDNIGHT, THEN VEERING SOUTHEAST LATE. WAVES CALM  
TO 2 FEET.    
WEDNESDAY  
SOUTHEAST WINDS 10 TO 20 KNOTS BACKING EAST BY MID  
AFTERNOON. WAVES CALM TO 2 FEET.    
WEDNESDAY NIGHT  
SOUTHEAST WINDS 10 TO 20 KNOTS VEERING SOUTH  
AFTER MIDNIGHT. WAVES BUILDING TO 1 TO 3 FEET, THEN SUBSIDING TO  
CALM TO 2 FEET.    
THURSDAY  
SOUTH WINDS 10 TO 20 KNOTS BECOMING SOUTHEAST 5 TO  
15 KNOTS BY MID AFTERNOON. WAVES CALM TO 2 FEET.    
THURSDAY NIGHT  
SOUTH WINDS 10 TO 20 KNOTS DIMINISHING TO 5 TO  
15 KNOTS AFTER MIDNIGHT. WAVES CALM TO 2 FEET.    
FRIDAY  
SOUTH WINDS 5 TO 15 KNOTS. WAVES CALM TO 2 FEET.    
SATURDAY  
SOUTHEAST WINDS 10 TO 20 KNOTS VEERING SOUTH. WAVES  
CALM TO 2 FEET.   
  
  
  
LSZ267-220800-  
LAKE SUPERIOR FROM GRAND MARAIS MI TO WHITEFISH POINT MI 5NM OFF  
SHORE TO THE US/CANADIAN BORDER-  
401 PM EDT MON SEP 21 2026  
   
LATE THIS AFTERNOON  
NORTHEAST WINDS 5 TO 15 KNOTS. WAVES CALM  
TO 2 FEET.    
TONIGHT  
NORTHEAST WINDS 10 TO 20 KNOTS VEERING EAST AFTER  
MIDNIGHT. WAVES CALM TO 2 FEET.    
TUESDAY  
EAST WINDS 10 TO 20 KNOTS DIMINISHING TO 5 TO 15 KNOTS  
IN THE AFTERNOON, THEN BACKING NORTHEAST LATE. WAVES CALM TO  
2 FEET.    
TUESDAY NIGHT  
NORTHEAST WINDS 5 TO 15 KNOTS BECOMING SOUTHEAST  
10 TO 20 KNOTS AFTER MIDNIGHT. WAVES CALM TO 2 FEET.    
WEDNESDAY  
SOUTHEAST WINDS 10 TO 20 KNOTS BACKING EAST BY MID  
AFTERNOON. WAVES CALM TO 2 FEET.    
WEDNESDAY NIGHT  
SOUTHEAST WINDS 10 TO 20 KNOTS. WAVES CALM TO  
2 FEET.    
THURSDAY  
SOUTHEAST WINDS 10 TO 20 KNOTS. WAVES CALM TO 2 FEET.   
THURSDAY NIGHT  
SOUTHEAST WINDS 10 TO 20 KNOTS BECOMING SOUTH  
5 TO 15 KNOTS AFTER MIDNIGHT. WAVES CALM TO 2 FEET.    
FRIDAY  
EAST WINDS 5 TO 15 KNOTS VEERING SOUTH. WAVES CALM TO  
2 FEET.    
SATURDAY  
SOUTHEAST WINDS 5 TO 15 KNOTS VEERING SOUTH. WAVES  
CALM TO 2 FEET.   
  
  
  
LSZ261-220200-  
MAFOR 2121/  
SUPERIOR WEST 11120 12220 12210 12200 11110. WAVES 1 TO 3 FEET.   
  
SUPERIOR NORTH CENTRAL 15200 11210 11310. WAVES 2 FEET OR LESS.   
  
SUPERIOR SOUTH CENTRAL 12110 14210 11220 11210. WAVES 1 TO 3  
FEET.   
  
SUPERIOR EAST 11100 11800 11110 14210 11200. WAVES 1 TO 2 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