World Resorts USA Dewey Beach Weather

Dewey Beach Sea Temperature in September

Average sea water temperature in September:
+73.1°F
Minimum sea water temperature in September: 79.5°F
Maximum sea water temperature in September: 68.4°F

Daily sea water temperature in September, °F

Show year:
2025
2024
2023

The average sea water temperature in September of 2025 was 72.6°F. The highest and lowest sea temperatures during the month were 74.8°F and 70.9°F.

Monthly sea water temperature in Dewey Beach, °F

Which USA resorts have warmest sea in September?

Place name September 2025 September 2024
Key West 86.9°F 87.4°F
Islamorada 86.7°F 87.3°F
Key Largo 86.6°F 87.1°F
Fort Lauderdale 86.4°F 86.4°F
West Palm Beach 86.2°F 86.4°F
Everglades 86.2°F 87.0°F
Miami Beach 86.1°F 86.3°F
Naples 86.1°F 87.2°F
Marco Island 86.0°F 87.2°F
South Padre Island 86.0°F 85.8°F
Corpus Christi 85.8°F 84.7°F
Miami 85.8°F 86.0°F
Sanibel Island 85.7°F 87.0°F
Galveston Island 85.5°F 84.4°F
Galveston 85.5°F 83.7°F
Cape Coral 85.2°F 86.5°F
Houston 84.9°F 83.4°F
Siesta Key 84.9°F 86.8°F
Sarasota 84.8°F 86.7°F
Cocoa Beach 84.6°F 85.2°F

Best time for vacation in Dewey Beach

Sunniest months:
November 18 days
October 16 days
June 14 days
Warmest months:
July 80.8 °F
August 78.4 °F
June 74.9 °F
Warmest sea temp:
July 75.4 °F
August 74.9 °F
September 73.1 °F
Coldest months:
January 41.2 °F
February 43.8 °F
December 46.4 °F
Rainiest months:
August 4 days
February 3 days
March 3 days
Windiest months:
March 13.3 mph
January 12.8 mph
April 12.5 mph

Dewey Beach on a weather map

Dewey Beach
+45°F
NE 9 mph
Feels like: +41°F
Precip.: 0%
Places in USA:
Name
°F
+50°F
+75°F
+75°F
+64°F
+59°F
+77°F
+79°F
+70°F
+37°F
+63°F
+57°F
+79°F
+77°F
+73°F
+41°F
24 Hours Forecast
Dewey Beach
Local time: 18:18
December 23, tuesday
2100
43°F
NE
12 mph
December 24, wednesday
0000
43°F
E
12 mph
0300
41°F
E
15 mph
0600
39°F
SE
20 mph
0900
39°F
SE
22 mph
1200
41°F
SE
22 mph
1500
41°F
SE
20 mph
1800
41°F
SE
14 mph
Units of measurement: °C / °F