Measurements:
°C
°F
Dewey Beach
84°F
N 13 mph
Feels like: 92°F
Precip: 10%
World Resorts USA Dewey Beach Weather

Dewey Beach Sea Water Temperature

Current Sea Water Temperature:
+78.2°F
Maximum Sea Water Temperature in August: 85.8°F
Minimum Sea Water Temperature in August: 71.6°F
Average water temperature in August: 77.7°F

Sea Water Temperature for the Last 10 Days:

August 05 78.2°F July 31 76.6°F
August 04 79.4°F July 30 75.8°F
August 03 79.0°F July 29 75.6°F
August 02 78.2°F July 28 78.0°F
August 01 77.2°F July 27 78.4°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: 2025 2024 2023

The average sea surface temperature in August 2025 for Dewey Beach was 79.4°F. The maximum and minimum values were 76.8°F and 85.8°F respectively.

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Dewey Beach was 75.2°F. The maximum and minimum values were 73.2°F and 77.6°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 81.5 °F
June 77.6 °F
Warmest sea temperature:
July 78.3 °F
August 77.7 °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 +94
Chicago +82
Hawaii +82
Houston +106
Las Vegas +124
Los Angeles +92
Maui +78
Miami +92
Myrtle Beach +84
New York +84
San Diego +80
San Francisco +62
Santa Monica +80
Sarasota +92
Washington +88
24 Hours Weather Forecast
Dewey Beach
Local time: 15:15
05 aug, wednesday
1800 86°F
N
15 mph
2100 78°F
N
12 mph
06 aug, thursday
0000 78°F
N
12 mph
0300 78°F
NE
9 mph
0600 78°F
NE
8 mph
0900 82°F
NE
11 mph
1200 84°F
N
12 mph
1500 86°F
N
12 mph