Marine Weather Forecast from Environment Canada

Winds


Issued 08:03 AM EDT 25 September 2020

Today Tonight and Saturday. Strong wind warning in effect. Wind south 15 knots increasing to south 25 this evening then veering to southwest 20 late overnight. Wind diminishing to southwest 15 early Saturday morning and to variable 10 late Saturday morning. Wind increasing to southeast 20 Saturday evening.

Extended Forecast


Issued 03:00 AM EDT 25 September 2020
Sunday Wind southeast 20 knots increasing to west 25 in the morning.
Monday Wind west 15 knots diminishing to light.
Tuesday Wind northwest 15 knots.

Waves


Issued 03:00 AM EDT 25 September 2020

Today Tonight and Saturday. Waves one half metre or less building to one near noon and to 2 near midnight. Waves subsiding to one Saturday morning.

Weather & Visibility


Issued 08:03 AM EDT 25 September 2020

Today Tonight and Saturday.Showers this morning. Showers tonight and Saturday morning with a risk of thunderstorms. Showers Saturday evening with a risk of thunderstorms. Fog patches.

Ice Forecast*


Issued 12:00 PM EDT 17 May 2020

Today Tonight and Monday Forecasts available to mariners upon request.

*Ice Forecast and Warnings also apply to U.S. waters

 

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



  
743  
FZUS63 KMQT 251358  
GLFLS  
 
OPEN LAKE FORECAST FOR LAKE SUPERIOR  
NATIONAL WEATHER SERVICE MARQUETTE MI  
958 AM EDT FRI SEP 25 2020  
 
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
 
LAKE SUPERIOR REMAINS BETWEEN A 30.1 INCH RIDGE OF  
HIGH PRESSURE OVER NEW ENGLAND AND A 29.2 INCH LOW PRESSURE SYSTEM  
OVER NORTHERN MANITOBA TODAY. A 29.6 INCH TROUGH THAT EXTENDS  
SOUTH FROM THAT LOW LIFT NORTHEASTWARD OVER LAKE SUPERIOR TONIGHT.  
SLIGHT RIDGING OF AROUND 29.7 INCHES RETURNS BRIEFLY SATURDAY  
MORNING, BUT A 29.5 INCH LOW DEVELOPING IN SOUTHERN MINNESOTA LATE  
SATURDAY AFTERNOON WILL LIFT NORTHEASTWARD ACROSS LAKE SUPERIOR  
SATURDAY EVENING WHILE DEEPENING TO AROUND 29.3 INCHES. THIS LOW  
WILL CONTINUE TO DEEPEN TO 29.1 INCHES BY LATE SUNDAY AS THE LOW  
REACHES NORTHERN QUEBEC. THIS LOW PRESSURE SYSTEM WILL EXTEND AN  
ELONGATED TROUGH OF 29.7 INCHES OVER LAKE SUPERIOR THROUGH MONDAY  
BEFORE WEAK RIDGING OVER 29.8 INCHES MOVES OVER THE LAKE MONDAY  
NIGHT. ANOTHER TROUGH OF 29.6 INCHES WILL MOVE OVER LAKE SUPERIOR  
ON TUESDAY.  
 
LSZ162-252200-  
LAKE SUPERIOR WEST OF A LINE FROM SAXON HARBOR WI TO GRAND  
PORTAGE MN BEYOND 5NM-  
958 AM EDT FRI SEP 25 2020 /858 AM CDT FRI SEP 25 2020/  
   
REST OF TODAY
 
SOUTH WINDS 5 TO 15 KNOTS BACKING EAST IN THE  
AFTERNOON, THEN BACKING NORTHEAST LATE. PATCHY FOG. A CHANCE OF  
SHOWERS AND THUNDERSTORMS BY MID AFTERNOON. WAVES CALM TO 2 FEET.   
TONIGHT
 
WEST WINDS 5 TO 15 KNOTS BACKING SOUTHWEST LATE. A  
CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH MIDNIGHT. PATCHY FOG.  
WAVES CALM TO 2 FEET.    
SATURDAY
 
SOUTHWEST WINDS 5 TO 15 KNOTS BACKING EAST IN THE  
AFTERNOON, THEN INCREASING TO 10 TO 20 KNOTS LATE. PATCHY FOG  
THROUGH EARLY AFTERNOON. A CHANCE OF SHOWERS AND A SLIGHT CHANCE  
OF THUNDERSTORMS BY MID AFTERNOON. WAVES CALM TO 2 FEET.    
SATURDAY NIGHT
 
NORTHEAST WINDS 10 TO 20 KNOTS BACKING WEST  
AFTER MIDNIGHT. SHOWERS LIKELY AND A SLIGHT CHANCE OF  
THUNDERSTORMS THROUGH MIDNIGHT, THEN A SLIGHT CHANCE OF SHOWERS  
AFTER MIDNIGHT. WAVES BUILDING TO 2 TO 4 FEET.    
SUNDAY
 
SOUTHWEST WINDS 15 TO 25 KNOTS VEERING WEST BY MID  
AFTERNOON. WAVES BUILDING TO 3 TO 5 FEET OCCASIONALLY TO 7 FEET,  
THEN SUBSIDING TO 2 TO 4 FEET.    
SUNDAY NIGHT
 
WEST WINDS 10 TO 20 KNOTS. WAVES SUBSIDING TO  
CALM TO 2 FEET.    
MONDAY
 
NORTHWEST WINDS 10 TO 20 KNOTS DIMINISHING TO 5 TO  
15 KNOTS. A CHANCE OF SHOWERS. WAVES CALM TO 2 FEET.    
TUESDAY
 
WEST WINDS 10 TO 20 KNOTS VEERING NORTHWEST. SHOWERS  
LIKELY, THEN A CHANCE OF SHOWERS. WAVES BUILDING TO 1 TO 3 FEET.  
 

 
 
LSZ263-252200-  
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-  
958 AM EDT FRI SEP 25 2020  
   
REST OF TODAY
 
SOUTH WINDS 5 TO 15 KNOTS BACKING EAST LATE. A  
CHANCE OF SHOWERS AND THUNDERSTORMS BY MID AFTERNOON. WAVES CALM  
TO 2 FEET.    
TONIGHT
 
WEST WINDS 5 TO 15 KNOTS. A CHANCE OF SHOWERS AND  
THUNDERSTORMS THROUGH MIDNIGHT. PATCHY FOG. WAVES BUILDING TO  
1 TO 3 FEET, THEN SUBSIDING TO CALM TO 2 FEET.    
SATURDAY
 
SOUTHWEST WINDS 5 TO 15 KNOTS BACKING SOUTH IN THE  
AFTERNOON, THEN BECOMING EAST 10 TO 20 KNOTS LATE. PATCHY FOG  
THROUGH EARLY AFTERNOON. A SLIGHT CHANCE OF SHOWERS AND  
THUNDERSTORMS BY MID AFTERNOON. WAVES CALM TO 2 FEET.    
SATURDAY NIGHT
 
EAST WINDS 10 TO 20 KNOTS BECOMING WEST 15 TO  
25 KNOTS AFTER MIDNIGHT. SHOWERS AND A SLIGHT CHANCE OF  
THUNDERSTORMS THROUGH MIDNIGHT, THEN A SLIGHT CHANCE OF SHOWERS  
AFTER MIDNIGHT. WAVES BUILDING TO 2 TO 4 FEET.    
SUNDAY
 
WEST WINDS 15 TO 25 KNOTS. WAVES BUILDING TO 4 TO  
7 FEET OCCASIONALLY TO 9 FEET, THEN SUBSIDING TO 3 TO 5 FEET  
OCCASIONALLY TO 7 FEET.    
SUNDAY NIGHT
 
WEST WINDS 15 TO 25 KNOTS DIMINISHING TO 10 TO  
20 KNOTS AFTER MIDNIGHT. WAVES SUBSIDING TO CALM TO 2 FEET.    
MONDAY
 
NORTHWEST WINDS 10 TO 20 KNOTS. A CHANCE OF SHOWERS.  
WAVES CALM TO 2 FEET.    
TUESDAY
 
WEST WINDS 10 TO 20 KNOTS VEERING NORTHWEST. SHOWERS  
LIKELY, THEN A CHANCE OF SHOWERS. WAVES BUILDING TO 2 TO 4 FEET.  
 

 
 
LSZ264-252200-  
LAKE SUPERIOR FROM UPPER ENTRANCE TO PORTAGE CANAL TO MANITOU  
ISLAND MI 5NM OFF SHORE TO THE US/CANADIAN BORDER-  
958 AM EDT FRI SEP 25 2020  
   
REST OF TODAY
 
SOUTH WINDS 5 TO 15 KNOTS BACKING SOUTHEAST  
LATE. PATCHY FOG. SHOWERS LIKELY AND A CHANCE OF THUNDERSTORMS BY  
MID AFTERNOON. WAVES CALM TO 2 FEET BUILDING TO 1 TO 3 FEET, THEN  
SUBSIDING TO CALM TO 2 FEET.    
TONIGHT
 
NORTH WINDS 5 TO 15 KNOTS BACKING WEST AFTER MIDNIGHT.  
SHOWERS AND A CHANCE OF THUNDERSTORMS THROUGH MIDNIGHT. PATCHY  
FOG. WAVES BUILDING TO 2 TO 4 FEET, THEN SUBSIDING TO 1 TO  
3 FEET.    
SATURDAY
 
SOUTHWEST WINDS 5 TO 15 KNOTS BACKING SOUTH IN THE  
AFTERNOON. PATCHY FOG THROUGH EARLY AFTERNOON. A SLIGHT CHANCE OF  
SHOWERS BY MID AFTERNOON. WAVES SUBSIDING TO CALM TO 2 FEET.    
SATURDAY NIGHT
 
EAST WINDS 10 TO 20 KNOTS BACKING NORTHWEST  
AFTER MIDNIGHT. SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS  
THROUGH MIDNIGHT, THEN A CHANCE OF SHOWERS AFTER MIDNIGHT. WAVES  
BUILDING TO 2 TO 4 FEET.    
SUNDAY
 
WEST WINDS 15 TO 25 KNOTS. WAVES BUILDING TO 4 TO  
7 FEET OCCASIONALLY TO 9 FEET, THEN SUBSIDING TO 3 TO 6 FEET  
OCCASIONALLY TO 8 FEET.    
SUNDAY NIGHT
 
WEST WINDS 10 TO 20 KNOTS DIMINISHING TO 5 TO  
15 KNOTS AFTER MIDNIGHT. WAVES SUBSIDING TO CALM TO 2 FEET.    
MONDAY
 
NORTHWEST WINDS 5 TO 15 KNOTS. A CHANCE OF SHOWERS.  
WAVES CALM TO 2 FEET.    
TUESDAY
 
WEST WINDS 5 TO 15 KNOTS VEERING NORTHWEST. A CHANCE  
OF SHOWERS. WAVES BUILDING TO 2 TO 4 FEET.  
 

 
 
LSZ265-252200-  
LAKE SUPERIOR WEST OF LINE FROM MANITOU ISLAND TO MARQUETTE MI  
BEYOND 5NM FROM SHORE-  
958 AM EDT FRI SEP 25 2020  
   
REST OF TODAY
 
SOUTH WINDS 10 TO 20 KNOTS BACKING SOUTHEAST IN  
THE AFTERNOON, THEN VEERING SOUTH LATE. A CHANCE OF SHOWERS AND A  
SLIGHT CHANCE OF THUNDERSTORMS BY MID AFTERNOON. WAVES CALM TO  
2 FEET BUILDING TO 1 TO 3 FEET.    
TONIGHT
 
SOUTH WINDS 15 TO 25 KNOTS VEERING WEST AFTER  
MIDNIGHT, THEN DIMINISHING TO 5 TO 15 KNOTS LATE. A CHANCE OF  
SHOWERS AND THUNDERSTORMS THROUGH MIDNIGHT. PATCHY FOG AFTER  
MIDNIGHT. WAVES BUILDING TO 2 TO 4 FEET, THEN SUBSIDING TO CALM TO  
2 FEET.    
SATURDAY
 
SOUTH WINDS 5 TO 15 KNOTS BACKING SOUTHEAST IN THE  
AFTERNOON, THEN INCREASING TO 10 TO 20 KNOTS LATE. PATCHY FOG  
THROUGH EARLY AFTERNOON. A SLIGHT CHANCE OF SHOWERS BY MID  
AFTERNOON. WAVES CALM TO 2 FEET.    
SATURDAY NIGHT
 
SOUTHEAST WINDS 15 TO 25 KNOTS VEERING WEST  
AFTER MIDNIGHT. SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS  
THROUGH MIDNIGHT, THEN A SLIGHT CHANCE OF SHOWERS AFTER MIDNIGHT.  
WAVES BUILDING TO 2 TO 4 FEET.    
SUNDAY
 
WEST WINDS 15 TO 25 KNOTS DIMINISHING TO 10 TO 20 KNOTS  
BY MID AFTERNOON. WAVES SUBSIDING TO CALM TO 2 FEET.    
SUNDAY NIGHT
 
WEST WINDS 10 TO 20 KNOTS. WAVES CALM TO 2 FEET.    
MONDAY
 
NORTHWEST WINDS 10 TO 20 KNOTS. A CHANCE OF SHOWERS.  
WAVES CALM TO 2 FEET.    
TUESDAY
 
WEST WINDS 10 TO 20 KNOTS VEERING NORTHWEST. SHOWERS  
LIKELY. WAVES CALM TO 2 FEET.  
 

 
 
LSZ266-252200-  
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-  
958 AM EDT FRI SEP 25 2020  
   
REST OF TODAY
 
SOUTH WINDS 10 TO 20 KNOTS INCREASING TO 15 TO  
25 KNOTS LATE. PATCHY FOG. A CHANCE OF SHOWERS BY MID AFTERNOON.  
WAVES CALM TO 2 FEET BUILDING TO 1 TO 3 FEET, THEN SUBSIDING TO  
CALM TO 2 FEET.    
TONIGHT
 
SOUTH WINDS 20 TO 30 KNOTS VEERING WEST AFTER  
MIDNIGHT, THEN DIMINISHING TO 5 TO 15 KNOTS LATE. PATCHY FOG. A  
CHANCE OF THUNDERSTORMS THROUGH MIDNIGHT. A CHANCE OF SHOWERS.  
WAVES BUILDING TO 3 TO 6 FEET OCCASIONALLY TO 8 FEET, THEN  
SUBSIDING TO 2 TO 4 FEET.    
SATURDAY
 
WEST WINDS 5 TO 15 KNOTS BACKING SOUTH IN THE  
AFTERNOON, THEN BECOMING SOUTHEAST 10 TO 20 KNOTS LATE. PATCHY  
DENSE FOG THROUGH EARLY AFTERNOON. WAVES SUBSIDING TO CALM TO  
2 FEET.    
SATURDAY NIGHT
 
SOUTHEAST WINDS 15 TO 25 KNOTS BECOMING WEST  
20 TO 30 KNOTS AFTER MIDNIGHT. SHOWERS AND A SLIGHT CHANCE OF  
THUNDERSTORMS THROUGH MIDNIGHT, THEN A CHANCE OF SHOWERS AFTER  
MIDNIGHT. WAVES BUILDING TO 3 TO 5 FEET OCCASIONALLY TO 7 FEET.    
SUNDAY
 
WEST WINDS 15 TO 25 KNOTS DIMINISHING TO 10 TO 20 KNOTS  
BY MID AFTERNOON. WAVES BUILDING TO 3 TO 6 FEET OCCASIONALLY TO  
8 FEET.    
SUNDAY NIGHT
 
WEST WINDS 10 TO 20 KNOTS. WAVES SUBSIDING TO  
1 TO 3 FEET.    
MONDAY
 
NORTHWEST WINDS 10 TO 20 KNOTS. A CHANCE OF SHOWERS.  
WAVES SUBSIDING TO CALM TO 2 FEET.    
TUESDAY
 
NORTHWEST WINDS 10 TO 20 KNOTS. A CHANCE OF SHOWERS,  
THEN SHOWERS LIKELY. WAVES BUILDING TO 1 TO 3 FEET.  
 

 
 
LSZ267-252200-  
LAKE SUPERIOR FROM GRAND MARAIS MI TO WHITEFISH POINT MI 5NM OFF  
SHORE TO THE US/CANADIAN BORDER-  
958 AM EDT FRI SEP 25 2020  
   
REST OF TODAY
 
SOUTH WINDS 10 TO 20 KNOTS INCREASING TO 15 TO  
25 KNOTS LATE. WAVES 1 TO 3 FEET SUBSIDING TO CALM TO 2 FEET,  
THEN BUILDING TO 1 TO 3 FEET.    
TONIGHT
 
SOUTH WINDS 20 TO 30 KNOTS VEERING SOUTHWEST AFTER  
MIDNIGHT, THEN BECOMING WEST 10 TO 20 KNOTS LATE. A CHANCE OF  
SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS. PATCHY FOG AFTER  
MIDNIGHT. WAVES BUILDING TO 3 TO 6 FEET OCCASIONALLY TO 8 FEET,  
THEN SUBSIDING TO 2 TO 4 FEET.    
SATURDAY
 
NORTHWEST WINDS 5 TO 15 KNOTS BACKING SOUTH IN THE  
AFTERNOON, THEN BECOMING SOUTHEAST 10 TO 20 KNOTS LATE. PATCHY  
FOG THROUGH EARLY AFTERNOON. A SLIGHT CHANCE OF SHOWERS BY MID  
AFTERNOON. WAVES SUBSIDING TO CALM TO 2 FEET.    
SATURDAY NIGHT
 
SOUTHEAST WINDS 15 TO 25 KNOTS BECOMING  
SOUTHWEST 20 TO 30 KNOTS AFTER MIDNIGHT. SHOWERS AND A SLIGHT  
CHANCE OF THUNDERSTORMS THROUGH MIDNIGHT, THEN A CHANCE OF  
SHOWERS AFTER MIDNIGHT. WAVES BUILDING TO 3 TO 6 FEET  
OCCASIONALLY TO 8 FEET.    
SUNDAY
 
WEST WINDS 15 TO 25 KNOTS BECOMING SOUTHWEST 10 TO  
20 KNOTS BY MID AFTERNOON. WAVES BUILDING TO 4 TO 7 FEET  
OCCASIONALLY TO 9 FEET, THEN SUBSIDING TO 2 TO 4 FEET.    
SUNDAY NIGHT
 
SOUTHWEST WINDS 10 TO 20 KNOTS VEERING WEST AFTER  
MIDNIGHT. WAVES SUBSIDING TO CALM TO 2 FEET.    
MONDAY
 
WEST WINDS 10 TO 20 KNOTS VEERING NORTHWEST. A CHANCE  
OF SHOWERS. WAVES CALM TO 2 FEET.    
TUESDAY
 
NORTHWEST WINDS 10 TO 20 KNOTS BACKING WEST. SHOWERS  
LIKELY. WAVES BUILDING TO 1 TO 3 FEET.  
 

 
LSZ261-252200-  
MAFOR 2515/  
SUPERIOR WEST 11300 11210 11116 11720 12600 12500. A CHANCE OF  
THUNDERSTORMS THIS AFTERNOON AND EVENING. WAVES 1 TO 2 FEET.  
 
SUPERIOR NORTH CENTRAL 11410 11310 11316 11416 13610 11500. A  
CHANCE OF THUNDERSTORMS THIS EVENING. WAVES 1 TO 3 FEET.  
 
SUPERIOR SOUTH CENTRAL 12310 11420 11430 11530 11620 11610 11500.  
A CHANCE OF SHOWERS AND THUNDERSTORMS TONIGHT. WAVES 1 TO 4 FEET  
THIS AFTERNOON AND TONIGHT. WAVES 2 FEET OR LESS SATURDAY  
MORNING.  
 
SUPERIOR EAST 12410 11420 11430 11436 11530 11620 11610. A CHANCE  
OF THUNDERSTORMS TONIGHT. WAVES 1 TO 3 FEET THIS AFTERNOON. WAVES  
2 TO 4 FEET BUILDING TO 4 TO 6 FEET TONIGHT. WAVES 2 TO 5 FEET  
SATURDAY MORNING.  
 

 
 
RJC  
 
EXPERIMENTAL MODERNIZED OPEN LAKE FORECAST IS AVAILABLE ONLINE AT  
WEATHER.GOV/MQT/GLFTABLE  
 
GRAPHICAL MARINE FORECASTS ARE AVAILABLE ONLINE AT:  
WEATHER.GOV/GREATLAKES  
 




Random Weather Facts

LIGHTNING
Generally, any and all of the various forms of visible electrical discharge produced by thunderstorms is known as lightning.