Marine Weather Forecast from Environment Canada

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

  
047   
FZUS63 KMQT 172001  
GLFLS   
  
OPEN LAKE FORECAST FOR LAKE SUPERIOR  
NATIONAL WEATHER SERVICE MARQUETTE MI  
401 PM EDT FRI JUL 17 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  
   
  
A 29.7 INCH LOW CROSSES LAKE SUPERIOR TONIGHT AND MOVES TO SOUTHERN   
QUEBEC BY SATURDAY AFTERNOON. WEAK RIDGING OF AROUND 30.0 INCHES   
RETURNS TO THE GREAT LAKES LATE SATURDAY AND PERSISTS THROUGH   
SUNDAY. A STRONG LOW RANGING FROM 29.1 TO 29.4 INCHES OVER NORTHERN   
ONTARIO LOOKS TO BRING TROUGHING OF AROUND 29.5 INCHES OVER LAKE   
SUPERIOR ON MONDAY.  
  
LSZ162-180800-  
LAKE SUPERIOR WEST OF A LINE FROM SAXON HARBOR WI TO GRAND  
PORTAGE MN BEYOND 5NM-  
401 PM EDT FRI JUL 17 2026 /301 PM CDT FRI JUL 17 2026/  
  
...DENSE SMOKE ADVISORY IN EFFECT UNTIL 6 AM EDT /5 AM CDT/  
SATURDAY...  
   
LATE THIS AFTERNOON  
EAST WINDS 5 TO 15 KNOTS. AREAS OF SMOKE.  
A CHANCE OF SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS. WAVES  
CALM TO 2 FEET.    
TONIGHT  
SOUTHWEST WINDS 10 TO 20 KNOTS VEERING WEST AFTER  
MIDNIGHT. A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH  
MIDNIGHT. AREAS OF SMOKE. WAVES CALM TO 2 FEET.    
SATURDAY  
NORTHWEST WINDS 5 TO 15 KNOTS BACKING SOUTHWEST IN  
THE AFTERNOON. PATCHY SMOKE. WAVES CALM TO 2 FEET.    
SATURDAY NIGHT  
SOUTHWEST WINDS 5 TO 15 KNOTS VEERING NORTH  
AFTER MIDNIGHT, THEN BECOMING NORTHEAST LESS THAN 10 KNOTS LATE.  
SMOKE. WAVES CALM TO 2 FEET.    
SUNDAY  
SOUTHWEST WINDS 5 TO 15 KNOTS. SMOKE THROUGH EARLY  
AFTERNOON. WAVES CALM TO 2 FEET.    
SUNDAY NIGHT  
SOUTHWEST WINDS 5 TO 15 KNOTS INCREASING TO 10 TO  
20 KNOTS AFTER MIDNIGHT. A CHANCE OF THUNDERSTORMS. SHOWERS  
LIKELY AFTER MIDNIGHT. WAVES CALM TO 2 FEET.    
MONDAY  
SOUTHWEST WINDS 15 TO 25 KNOTS BECOMING WEST 20 TO  
30 KNOTS BY MID AFTERNOON. A CHANCE OF SHOWERS. WAVES BUILDING TO  
3 TO 5 FEET OCCASIONALLY TO 7 FEET, THEN SUBSIDING TO 2 TO  
4 FEET.    
MONDAY NIGHT  
WEST WINDS 20 TO 30 KNOTS DIMINISHING TO 15 TO  
25 KNOTS AFTER MIDNIGHT. A CHANCE OF SHOWERS. WAVES SUBSIDING TO  
1 TO 3 FEET, THEN BUILDING TO 2 TO 4 FEET.    
TUESDAY  
NORTHWEST WINDS 20 TO 30 KNOTS DIMINISHING TO 10 TO  
20 KNOTS. WAVES SUBSIDING TO CALM TO 2 FEET.    
WEDNESDAY  
SOUTHWEST WINDS 5 TO 15 KNOTS VEERING WEST. WAVES  
CALM TO 2 FEET.   
  
  
  
LSZ263-180800-  
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 FRI JUL 17 2026  
   
..DENSE SMOKE ADVISORY IN EFFECT UNTIL 6 AM EDT SATURDAY  
  
   
LATE THIS AFTERNOON  
EAST WINDS 5 TO 15 KNOTS. SMOKE. A CHANCE  
OF SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS. WAVES CALM TO  
2 FEET.    
TONIGHT  
WEST WINDS 5 TO 15 KNOTS. A CHANCE OF SHOWERS AND  
THUNDERSTORMS THROUGH MIDNIGHT. SMOKE. WAVES BUILDING TO 1 TO  
3 FEET.    
SATURDAY  
NORTHWEST WINDS 5 TO 15 KNOTS BACKING SOUTHWEST LATE.  
PATCHY SMOKE. WAVES SUBSIDING TO CALM TO 2 FEET.    
SATURDAY NIGHT  
WEST WINDS 5 TO 15 KNOTS BACKING SOUTHEAST  
AFTER MIDNIGHT, THEN VEERING SOUTH LATE. AREAS OF SMOKE. WAVES  
CALM TO 2 FEET.    
SUNDAY  
SOUTH WINDS 5 TO 15 KNOTS. SMOKE THROUGH EARLY  
AFTERNOON. WAVES CALM TO 2 FEET.    
SUNDAY NIGHT  
SOUTH WINDS 10 TO 20 KNOTS BECOMING SOUTHWEST  
15 TO 25 KNOTS AFTER MIDNIGHT. A CHANCE OF SHOWERS. WAVES  
BUILDING TO 2 TO 4 FEET.    
MONDAY  
SOUTHWEST WINDS 20 TO 30 KNOTS. A CHANCE OF SHOWERS  
THROUGH EARLY AFTERNOON. SHOWERS LIKELY BY MID AFTERNOON. WAVES  
BUILDING TO 3 TO 5 FEET OCCASIONALLY TO 7 FEET.    
MONDAY NIGHT  
WEST WINDS 15 TO 25 KNOTS INCREASING TO 20 TO  
30 KNOTS AFTER MIDNIGHT. A CHANCE OF SHOWERS. WAVES SUBSIDING TO  
2 TO 4 FEET, THEN BUILDING TO 3 TO 6 FEET OCCASIONALLY TO 8 FEET.   
TUESDAY  
NORTHWEST WINDS 20 TO 30 KNOTS DIMINISHING TO 15 TO  
25 KNOTS. WAVES SUBSIDING TO 1 TO 3 FEET.    
WEDNESDAY  
NORTHWEST WINDS 10 TO 20 KNOTS BECOMING WEST 5 TO  
15 KNOTS. WAVES SUBSIDING TO CALM TO 2 FEET.   
  
  
  
LSZ264-180800-  
LAKE SUPERIOR FROM UPPER ENTRANCE TO PORTAGE CANAL TO MANITOU  
ISLAND MI 5NM OFF SHORE TO THE US/CANADIAN BORDER-  
401 PM EDT FRI JUL 17 2026  
   
..DENSE SMOKE ADVISORY IN EFFECT UNTIL 6 AM EDT SATURDAY  
  
   
LATE THIS AFTERNOON  
SOUTHEAST WINDS 5 TO 15 KNOTS. SMOKE. A  
CHANCE OF SHOWERS AND THUNDERSTORMS. WAVES 1 TO 3 FEET.    
TONIGHT  
SOUTHEAST WINDS 5 TO 15 KNOTS VEERING WEST AFTER  
MIDNIGHT, THEN BECOMING NORTHWEST 10 TO 20 KNOTS LATE. A CHANCE  
OF SHOWERS AND THUNDERSTORMS THROUGH MIDNIGHT. SMOKE. WAVES  
BUILDING TO 2 TO 4 FEET.    
SATURDAY  
NORTHWEST WINDS 10 TO 20 KNOTS DIMINISHING TO 5 TO  
15 KNOTS IN THE AFTERNOON, THEN BACKING WEST LATE. SMOKE. WAVES  
SUBSIDING TO CALM TO 2 FEET.    
SATURDAY NIGHT  
WEST WINDS 5 TO 15 KNOTS BACKING SOUTH LATE.  
AREAS OF SMOKE. WAVES CALM TO 2 FEET.    
SUNDAY  
SOUTH WINDS 5 TO 15 KNOTS. AREAS OF SMOKE THROUGH EARLY  
AFTERNOON. WAVES CALM TO 2 FEET.    
SUNDAY NIGHT  
SOUTH WINDS 10 TO 20 KNOTS BECOMING SOUTHWEST  
15 TO 25 KNOTS AFTER MIDNIGHT. A CHANCE OF SHOWERS. WAVES  
BUILDING TO 2 TO 4 FEET.    
MONDAY  
SOUTHWEST WINDS 15 TO 25 KNOTS INCREASING TO 20 TO  
30 KNOTS BY MID AFTERNOON. SHOWERS LIKELY AND A CHANCE OF  
THUNDERSTORMS. WAVES BUILDING TO 3 TO 5 FEET OCCASIONALLY TO  
7 FEET.    
MONDAY NIGHT  
WEST WINDS 15 TO 25 KNOTS INCREASING TO 20 TO  
30 KNOTS AFTER MIDNIGHT. A CHANCE OF SHOWERS. WAVES SUBSIDING TO  
2 TO 4 FEET, THEN BUILDING TO 3 TO 5 FEET OCCASIONALLY TO 7 FEET.   
TUESDAY  
NORTHWEST WINDS 20 TO 30 KNOTS DIMINISHING TO 15 TO  
25 KNOTS. WAVES BUILDING TO 3 TO 6 FEET OCCASIONALLY TO 8 FEET,  
THEN SUBSIDING TO 2 TO 4 FEET.    
WEDNESDAY  
NORTHWEST WINDS 10 TO 20 KNOTS BECOMING WEST 5 TO  
15 KNOTS. WAVES SUBSIDING TO CALM TO 2 FEET.   
  
  
  
LSZ265-180800-  
LAKE SUPERIOR WEST OF LINE FROM MANITOU ISLAND TO MARQUETTE MI  
BEYOND 5NM FROM SHORE-  
401 PM EDT FRI JUL 17 2026  
   
..DENSE SMOKE ADVISORY IN EFFECT UNTIL 6 AM EDT SATURDAY  
  
   
LATE THIS AFTERNOON  
SOUTHEAST WINDS 10 TO 20 KNOTS. SMOKE. A  
CHANCE OF SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS. WAVES  
1 TO 3 FEET.    
TONIGHT  
SOUTH WINDS 10 TO 20 KNOTS BECOMING WEST 15 TO  
25 KNOTS AFTER MIDNIGHT, THEN INCREASING TO 20 TO 30 KNOTS LATE.  
A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH MIDNIGHT. SMOKE.  
WAVES BUILDING TO 2 TO 4 FEET.    
SATURDAY  
NORTHWEST WINDS 20 TO 30 KNOTS DIMINISHING TO 10 TO  
20 KNOTS. SMOKE. WAVES BUILDING TO 3 TO 5 FEET OCCASIONALLY TO  
7 FEET, THEN SUBSIDING TO 1 TO 3 FEET.    
SATURDAY NIGHT  
NORTHWEST WINDS 10 TO 20 KNOTS DIMINISHING TO  
5 TO 15 KNOTS AFTER MIDNIGHT, THEN BACKING SOUTH LATE. AREAS OF  
SMOKE. WAVES SUBSIDING TO CALM TO 2 FEET.    
SUNDAY  
SOUTH WINDS 5 TO 15 KNOTS BECOMING SOUTHEAST 10 TO  
20 KNOTS BY MID AFTERNOON. AREAS OF SMOKE THROUGH EARLY  
AFTERNOON. WAVES CALM TO 2 FEET.    
SUNDAY NIGHT  
SOUTH WINDS 10 TO 20 KNOTS BECOMING SOUTHWEST  
20 TO 30 KNOTS AFTER MIDNIGHT. A CHANCE OF SHOWERS AFTER  
MIDNIGHT. WAVES BUILDING TO 1 TO 3 FEET.    
MONDAY  
SOUTHWEST WINDS 20 TO 30 KNOTS. SHOWERS LIKELY AND A  
CHANCE OF THUNDERSTORMS. WAVES BUILDING TO 2 TO 4 FEET.    
MONDAY NIGHT  
WEST WINDS 20 TO 30 KNOTS INCREASING TO GALES TO  
35 KNOTS AFTER MIDNIGHT. A CHANCE OF SHOWERS. WAVES BUILDING TO  
4 TO 7 FEET OCCASIONALLY TO 9 FEET.    
TUESDAY  
NORTHWEST GALES TO 45 KNOTS. WAVES BUILDING TO 7 TO  
10 FEET OCCASIONALLY TO 13 FEET, THEN 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.   
  
  
  
LSZ266-180800-  
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 FRI JUL 17 2026  
   
..DENSE SMOKE ADVISORY IN EFFECT UNTIL 6 AM EDT SATURDAY  
  
   
LATE THIS AFTERNOON  
SOUTHEAST WINDS 15 TO 25 KNOTS. SMOKE. A  
CHANCE OF SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS. WAVES  
1 TO 3 FEET.    
TONIGHT  
SOUTH WINDS 10 TO 20 KNOTS VEERING WEST AFTER  
MIDNIGHT, THEN BECOMING NORTHWEST 15 TO 25 KNOTS LATE. SMOKE.  
SHOWERS LIKELY AND A CHANCE OF THUNDERSTORMS THROUGH MIDNIGHT. A  
SLIGHT CHANCE OF SHOWERS AFTER MIDNIGHT. WAVES BUILDING TO 2 TO  
4 FEET.    
SATURDAY  
NORTHWEST WINDS 15 TO 25 KNOTS. SMOKE. WAVES BUILDING  
TO 3 TO 5 FEET OCCASIONALLY TO 7 FEET, THEN SUBSIDING TO 2 TO  
4 FEET.    
SATURDAY NIGHT  
NORTHWEST WINDS 10 TO 20 KNOTS BECOMING NORTH  
5 TO 15 KNOTS AFTER MIDNIGHT, THEN VEERING SOUTH LATE. SMOKE.  
WAVES SUBSIDING TO CALM TO 2 FEET.    
SUNDAY  
SOUTH WINDS 5 TO 15 KNOTS. AREAS OF SMOKE THROUGH EARLY  
AFTERNOON. WAVES CALM TO 2 FEET.    
SUNDAY NIGHT  
SOUTH WINDS 10 TO 20 KNOTS INCREASING TO 15 TO  
25 KNOTS AFTER MIDNIGHT. A CHANCE OF SHOWERS AFTER MIDNIGHT.  
WAVES BUILDING TO 2 TO 4 FEET.    
MONDAY  
SOUTH WINDS 20 TO 30 KNOTS DIMINISHING TO 15 TO  
25 KNOTS BY MID AFTERNOON. SHOWERS AND A CHANCE OF THUNDERSTORMS.  
WAVES BUILDING TO 3 TO 5 FEET OCCASIONALLY TO 7 FEET.    
MONDAY NIGHT  
WEST WINDS 15 TO 25 KNOTS INCREASING TO GALES TO  
35 KNOTS AFTER MIDNIGHT. SHOWERS LIKELY THROUGH MIDNIGHT. WAVES  
SUBSIDING TO 2 TO 4 FEET, THEN BUILDING TO 4 TO 7 FEET  
OCCASIONALLY TO 9 FEET.    
TUESDAY  
NORTHWEST GALES TO 40 KNOTS. WAVES BUILDING TO 9 TO  
12 FEET OCCASIONALLY TO 15 FEET, THEN SUBSIDING TO 6 TO 9 FEET  
OCCASIONALLY TO 11 FEET.    
WEDNESDAY  
NORTHWEST GALES TO 35 KNOTS BECOMING WEST 10 TO  
20 KNOTS. WAVES SUBSIDING TO CALM TO 2 FEET.   
  
  
  
LSZ267-180800-  
LAKE SUPERIOR FROM GRAND MARAIS MI TO WHITEFISH POINT MI 5NM OFF  
SHORE TO THE US/CANADIAN BORDER-  
401 PM EDT FRI JUL 17 2026  
   
..DENSE SMOKE ADVISORY IN EFFECT UNTIL 6 AM EDT SATURDAY  
  
   
LATE THIS AFTERNOON  
SOUTHEAST WINDS 10 TO 20 KNOTS. SMOKE. A  
CHANCE OF SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS. WAVES  
CALM TO 2 FEET.    
TONIGHT  
SOUTH WINDS 15 TO 25 KNOTS VEERING WEST LATE. SMOKE.  
SHOWERS THROUGH MIDNIGHT. A CHANCE OF THUNDERSTORMS. A CHANCE OF  
SHOWERS AFTER MIDNIGHT. WAVES BUILDING TO 2 TO 4 FEET.    
SATURDAY  
NORTHWEST WINDS 15 TO 25 KNOTS. SMOKE. WAVES BUILDING  
TO 3 TO 5 FEET OCCASIONALLY TO 7 FEET.    
SATURDAY NIGHT  
NORTHWEST WINDS 10 TO 20 KNOTS BECOMING NORTH  
5 TO 15 KNOTS AFTER MIDNIGHT, THEN BACKING WEST LATE. SMOKE  
THROUGH MIDNIGHT, THEN PATCHY SMOKE AFTER MIDNIGHT. WAVES  
SUBSIDING TO CALM TO 2 FEET.    
SUNDAY  
SOUTH WINDS 5 TO 15 KNOTS BACKING SOUTHEAST BY MID  
AFTERNOON. PATCHY SMOKE THROUGH EARLY AFTERNOON. WAVES CALM TO  
2 FEET.    
SUNDAY NIGHT  
SOUTH WINDS 10 TO 20 KNOTS INCREASING TO 15 TO  
25 KNOTS AFTER MIDNIGHT. WAVES BUILDING TO 2 TO 4 FEET.    
MONDAY  
SOUTH WINDS 15 TO 25 KNOTS. A CHANCE OF SHOWERS THROUGH  
EARLY AFTERNOON. A CHANCE OF THUNDERSTORMS. SHOWERS BY MID  
AFTERNOON. WAVES 2 TO 4 FEET.    
MONDAY NIGHT  
SOUTHWEST WINDS 15 TO 25 KNOTS VEERING WEST AFTER  
MIDNIGHT. SHOWERS LIKELY AND A CHANCE OF THUNDERSTORMS THROUGH  
MIDNIGHT, THEN A CHANCE OF SHOWERS AFTER MIDNIGHT. WAVES BUILDING  
TO 3 TO 5 FEET OCCASIONALLY TO 7 FEET.    
TUESDAY  
NORTHWEST GALES TO 35 KNOTS. WAVES BUILDING TO 7 TO  
10 FEET OCCASIONALLY TO 13 FEET, THEN SUBSIDING TO 5 TO 8 FEET  
OCCASIONALLY TO 10 FEET.    
WEDNESDAY  
NORTHWEST WINDS 20 TO 30 KNOTS BECOMING WEST 5 TO  
15 KNOTS. WAVES SUBSIDING TO CALM TO 2 FEET.   
  
  
  
LSZ261-180200-  
MAFOR 1721/  
SUPERIOR WEST 11200 11810 12610 12710 11700 11500. A CHANCE OF  
SHOWERS THIS EVENING. WAVES 2 FEET OR LESS.   
  
SUPERIOR NORTH CENTRAL 12316 11510 11620 13720 11710. A CHANCE OF  
THUNDERSTORMS THIS EVENING. WAVES 1 TO 3 FEET TONIGHT. WAVES 2 TO  
4 FEET SUBSIDING TO 1 TO 2 FEET SATURDAY.   
  
SUPERIOR SOUTH CENTRAL 11320 11426 11520 11630 14730. A CHANCE OF  
THUNDERSTORMS TONIGHT. WAVES 2 TO 4 FEET TONIGHT. WAVES 3 TO 5  
FEET SUBSIDING TO 2 TO 4 FEET SATURDAY.   
  
SUPERIOR EAST 11310 11326 11426 11520 11720 11730 12720. A CHANCE  
OF THUNDERSTORMS TONIGHT. WAVES 1 TO 3 FEET BUILDING TO 2 TO 4  
FEET TONIGHT. WAVES 3 TO 5 FEET SATURDAY.   
  
  
  
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