Measurements:
°C
°F
Duluth
40°F
W 11 mph
Feels like: 34°F
Precip: 20%
World Resorts USA Duluth Weather

Duluth Sea Water Temperature

Current Sea Water Temperature:
+52.6°F
Maximum Sea Water Temperature in October: 67.4°F
Minimum Sea Water Temperature in October: 42.2°F
Average water temperature in October: 55.6°F

Sea Water Temperature for the Last 10 Days:

October 26 52.6°F October 21 53.0°F
October 25 53.0°F October 20 53.8°F
October 24 52.8°F October 19 54.4°F
October 23 53.6°F October 18 55.0°F
October 22 53.0°F October 17 55.2°F

When is the Warmest Sea for Duluth?

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

Average Water Temperature by Month, °F

Sea Water Temperature in August

Select Year: 2026 2025 2024

The average sea surface temperature in August 2026 for Duluth was 66.6°F. The maximum and minimum values were 61.6°F and 71.6°F respectively.

Sea Water Temperature in July

Select Year: 2026 2025 2024

The average sea surface temperature in July 2026 for Duluth was 66.0°F. The maximum and minimum values were 55.0°F and 75.8°F respectively.

Sea Water Temperature in September

Select Year: 2026 2025 2024

The average sea surface temperature in September 2026 for Duluth was 63.7°F. The maximum and minimum values were 58.8°F and 69.8°F respectively.

Best Time to Visit Duluth
The most sunny months:
August 14 days
July 13 days
May 12 days
The most warm months:
July 77.5 °F
August 75.8 °F
June 69.8 °F
Warmest sea temperature:
August 67.5 °F
July 65.5 °F
September 63.7 °F
The most cold months:
January 14.4 °F
February 16.7 °F
December 21.4 °F
The most rainy months:
August 3 days
July 3 days
June 2 days
The most windy months:
April 9 mph
March 8 mph
November 8 mph

Duluth on the Weather Map

USA Resorts:
NAME
F°
Boston +58
Chicago +58
Hawaii +80
Houston +76
Las Vegas +64
Los Angeles +74
Maui +72
Miami +82
New York +62
Panama City Beach +66
San Diego +74
San Francisco +60
Santa Monica +72
Tampa +74
Washington +56
24 Hours Weather Forecast
Duluth
Local time: 21:40
27 oct, tuesday
0000 40°F
W
11 mph
0300 40°F
W
13 mph
0600 40°F
W
14 mph
0900 42°F
W
14 mph
1200 42°F
W
13 mph
1500 44°F
W
9 mph
1800 46°F
W
6 mph
2100 46°F
SW
4 mph