Measurements:
°C
°F
Mount Desert Island
0°F
SE 17 mph
Feels like: -18°F
Precip: 0%
World Resorts USA Mount Desert Island Weather

Mount Desert Island Sea Water Temperature

Current Sea Water Temperature:
+46.0°F
Maximum Sea Water Temperature in December: 48.2°F
Minimum Sea Water Temperature in December: 40.0°F
Average water temperature in December: 44.1°F

Sea Water Temperature for the Last 10 Days:

December 04 46.0°F November 29 46.8°F
December 03 46.0°F November 28 47.2°F
December 02 45.6°F November 27 47.4°F
December 01 46.2°F November 26 47.0°F
November 30 47.0°F November 25 47.6°F

When is the Warmest Sea for Mount Desert Island?

According to our data for the last three years for Mount Desert Island 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: 2025 2024 2023

The average sea surface temperature in August 2025 for Mount Desert Island was 61.4°F. The maximum and minimum values were 57.8°F and 64.4°F respectively.

Sea Water Temperature in July

Select Year: 2025 2024 2023

The average sea surface temperature in July 2025 for Mount Desert Island was 59.1°F. The maximum and minimum values were 55.4°F and 61.8°F respectively.

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Mount Desert Island was 59.6°F. The maximum and minimum values were 57.4°F and 61.8°F respectively.

Best Time to Visit Mount Desert Island
The most sunny months:
September 13 days
November 13 days
October 13 days
The most warm months:
July 74.4 °F
August 73.7 °F
June 68.2 °F
Warmest sea temperature:
August 62.9 °F
July 60.9 °F
September 59.6 °F
The most cold months:
January 27.1 °F
February 27.7 °F
December 34.2 °F
The most rainy months:
December 3 days
October 3 days
March 2 days
The most windy months:
February 11 mph
March 10 mph
November 10 mph

Mount Desert Island on the Weather Map

USA Resorts:
NAME
Chicago 0
Hawaii +78
Honolulu +78
Houston +46
Las Vegas +40
Los Angeles +52
Maui +72
Miami +72
Miami Beach +80
New York +18
San Diego +54
San Francisco +46
Sarasota +62
Tampa +62
Washington +28
24 Hours Weather Forecast
Mount Desert Island
Local time: 01:43
05 dec, friday
0300 0°F
SE
17 mph
0600 -2°F
SE
14 mph
0900 4°F
SE
12 mph
1200 14°F
E
11 mph
1500 20°F
E
10 mph
1800 24°F
E
6 mph
2100 22°F
E
7 mph
06 dec, saturday
0000 20°F
E
5 mph