Measurements:
°C
°F
Dewey Beach
74°F
SW 14 mph
Feels like: 74°F
Precip: 4%
World Resorts USA Dewey Beach Weather

Dewey Beach Sea Water Temperature

Current Sea Water Temperature:
+79.0°F
Maximum Sea Water Temperature in September: 82.8°F
Minimum Sea Water Temperature in September: 70.4°F
Average water temperature in September: 76.0°F

Sea Water Temperature for the Last 10 Days:

September 15 79.0°F September 10 80.6°F
September 14 79.6°F September 09 80.4°F
September 13 78.6°F September 08 80.4°F
September 12 78.0°F September 07 80.2°F
September 11 80.0°F September 06 81.6°F

When is the Warmest Sea for Dewey Beach?

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

Average Water Temperature by Month, °F

Sea Water Temperature in July

Select Year: 2026 2025 2024

The average sea surface temperature in July 2026 for Dewey Beach was 79.0°F. The maximum and minimum values were 75.2°F and 84.0°F respectively.

Sea Water Temperature in August

Select Year: 2026 2025 2024

The average sea surface temperature in August 2026 for Dewey Beach was 80.4°F. The maximum and minimum values were 77.2°F and 84.4°F respectively.

Sea Water Temperature in September

Select Year: 2026 2025 2024

The average sea surface temperature in September 2026 for Dewey Beach was 79.7°F. The maximum and minimum values were 77.4°F and 82.0°F respectively.

Best Time to Visit Dewey Beach
The most sunny months:
November 18 days
October 16 days
June 15 days
The most warm months:
July 84.1 °F
August 81.6 °F
June 77.6 °F
Warmest sea temperature:
July 78.3 °F
August 78.1 °F
September 75.6 °F
The most cold months:
January 39.5 °F
February 41.8 °F
December 45.1 °F
The most rainy months:
August 4 days
February 3 days
March 3 days
The most windy months:
March 13 mph
January 13 mph
February 12 mph

Dewey Beach on the Weather Map

USA Resorts:
NAME
Boston +62
Chicago +66
Hawaii +80
Las Vegas +80
Los Angeles +72
Maui +66
Miami +88
Myrtle Beach +78
New York +66
Panama City Beach +90
San Diego +70
San Francisco +60
Santa Monica +70
Sarasota +86
Washington +66
24 Hours Weather Forecast
Dewey Beach
Local time: 10:30
15 sep, tuesday
1200 74°F
W
14 mph
1500 72°F
W
9 mph
1800 72°F
W
10 mph
2100 74°F
W
11 mph
16 sep, wednesday
0000 72°F
NW
11 mph
0300 72°F
NW
6 mph
0600 72°F
NW
4 mph
0900 72°F
W
4 mph