Average sea water temperature in September:
+86.1°F
| Minimum sea water temperature in September: | 89.6°F |
| Maximum sea water temperature in September: | 82.8°F |
Daily sea water temperature in September, °F
Show year:
2025
2024
2023
The average sea water temperature in September of 2025 was 86.9°F. The highest and lowest sea temperatures during the month were 89.2°F and 85.3°F.
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Monthly sea water temperature in Key West, °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 |
| 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 |
| Tampa | 84.3°F | 86.0°F |
Best time for vacation in Key West
Key West on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Key West
Local time: 15:03
December 30, tuesday
1800
66°F
S
21 mph
21 mph
2100
68°F
S
19 mph
19 mph
December 31, wednesday
0000
68°F
S
18 mph
18 mph
0300
66°F
S
18 mph
18 mph
0600
64°F
S
19 mph
19 mph
0900
64°F
S
20 mph
20 mph
1200
66°F
S
16 mph
16 mph
1500
66°F
S
14 mph
14 mph
