Measurements:
°C
°F
Grand Marais
12°F
S 9 mph
Feels like: -8°F
Precip: 0%
World Resorts USA Grand Marais Weather

Grand Marais Sea Water Temperature

Current Sea Water Temperature:
+30.2°F
Maximum Sea Water Temperature in February: 36.2°F
Minimum Sea Water Temperature in February: 30.2°F
Average water temperature in February: 33.1°F

Sea Water Temperature for the Last 10 Days:

February 21 30.2°F February 16 30.4°F
February 20 30.2°F February 15 30.4°F
February 19 30.2°F February 14 30.4°F
February 18 30.2°F February 13 30.4°F
February 17 30.4°F February 12 30.4°F

When is the Warmest Sea for Grand Marais?

According to our data for the last three years for Grand Marais the highest average sea water temperature was in August, September and October.

Average Water Temperature by Month, °F

Sea Water Temperature in August

Select Year: 2025 2024 2023

The average sea surface temperature in August 2025 for Grand Marais was 62.5°F. The maximum and minimum values were 56.6°F and 67.4°F respectively.

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Grand Marais was 59.5°F. The maximum and minimum values were 55.6°F and 64.2°F respectively.

Sea Water Temperature in October

Select Year: 2025 2024 2023

The average sea surface temperature in October 2025 for Grand Marais was 54.2°F. The maximum and minimum values were 49.6°F and 61.4°F respectively.

Best Time to Visit Grand Marais
The most sunny months:
September 14 days
August 13 days
July 12 days
The most warm months:
August 70.1 °F
July 69.0 °F
September 63.5 °F
Warmest sea temperature:
August 61.3 °F
September 60.2 °F
October 53.1 °F
The most cold months:
January 15.2 °F
February 15.4 °F
December 22.1 °F
The most rainy months:
August 3 days
April 2 days
July 2 days
The most windy months:
November 10 mph
December 9 mph
April 9 mph

Grand Marais on the Weather Map

USA Resorts:
NAME
Chicago +28
Hawaii +70
Honolulu +70
Houston +74
Las Vegas +34
Los Angeles +40
Maui +66
Miami +74
Miami Beach +78
New York +38
San Diego +44
San Francisco +42
Sarasota +68
Tampa +70
Washington +38
24 Hours Weather Forecast
Grand Marais
Local time: 08:45
21 feb, saturday
0900 12°F
S
9 mph
1200 16°F
S
7 mph
1500 18°F
S
9 mph
1800 18°F
SE
6 mph
2100 14°F
SE
7 mph
22 feb, sunday
0000 14°F
SE
11 mph
0300 12°F
SE
12 mph
0600 12°F
SE
13 mph