Measurements:
°C
°F
Dewey Beach
70°F
NE 6 mph
Feels like: 70°F
Precip: 10%
World Resorts USA Dewey Beach Weather

Dewey Beach Sea Water Temperature

Current Sea Water Temperature:
+70.4°F
Maximum Sea Water Temperature in June: 83.0°F
Minimum Sea Water Temperature in June: 62.0°F
Average water temperature in June: 70.2°F

Sea Water Temperature for the Last 10 Days:

June 24 70.4°F June 19 74.0°F
June 23 72.8°F June 18 73.4°F
June 22 74.0°F June 17 72.0°F
June 21 72.8°F June 16 76.0°F
June 20 73.4°F June 15 77.4°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: 2025 2024 2023

The average sea surface temperature in July 2025 for Dewey Beach was 80.7°F. The maximum and minimum values were 77.2°F and 83.4°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
January 14 days
The most warm months:
July 84.2 °F
August 81.5 °F
June 77.7 °F
Warmest sea temperature:
July 78.2 °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
Chicago +66
Hawaii +80
Honolulu +80
Houston +82
Las Vegas +96
Los Angeles +66
Maui +74
Miami +80
Miami Beach +88
Myrtle Beach +78
New York +70
San Diego +68
San Francisco +58
Sarasota +84
Tampa +84
24 Hours Weather Forecast
Dewey Beach
Local time: 00:11
25 jun, thursday
0300 70°F
NE
9 mph
0600 70°F
NE
7 mph
0900 74°F
N
7 mph
1200 76°F
N
12 mph
1500 78°F
N
17 mph
1800 76°F
N
19 mph
2100 74°F
N
17 mph
26 jun, friday
0000 74°F
N
18 mph