19.09
sat
sat
Day
84°F
W 8 mph
Precip.
23%
23%
Night
84°F
W 11 mph
Precip.
23%
23%
20.09
sun
sun
Day
84°F
N 6 mph
Precip.
4%
4%
Night
84°F
NW 9 mph
Precip.
37%
37%
21.09
mon
mon
Day
84°F
N 4 mph
Precip.
5%
5%
Night
84°F
NW 11 mph
Precip.
16%
16%
22.09
tue
tue
Day
84°F
SW 4 mph
Precip.
7%
7%
Night
84°F
NW 5 mph
Precip.
16%
16%
23.09
wed
wed
Day
82°F
NW 6 mph
Precip.
20%
20%
Night
82°F
W 17 mph
Precip.
44%
44%
24.09
thu
thu
Day
82°F
NW 14 mph
Precip.
51%
51%
Night
82°F
NW 12 mph
Precip.
7%
7%
25.09
fri
fri
Day
82°F
SW 6 mph
Precip.
23%
23%
Night
84°F
W 9 mph
Precip.
8%
8%
sea water
temperature
temperature
| Key West |
monthly
weather
weather
| Key West |
current
weather
weather
| Key West |
14 days
forecast
forecast
| Key West |
Sea water temperature in September, °F
Show year:
2026
2025
2024
The average sea water temperature in September of 2026 was 88.5°F. The highest and lowest sea temperatures during the month were 89.4°F and 87.1°F.
Sea water temperature in October, °F
Show year:
2025
2024
2023
The average sea water temperature in October of 2025 was 83.8°F. The highest and lowest sea temperatures during the month were 86.4°F and 81.5°F.
Air temperature in Key West, °F
Precipitation total in Key West, in.
* Charts above show average data for the last 3 years.
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: 05:16
September 19, saturday
0600
84°F
W
7 mph
7 mph
0900
84°F
SW
8 mph
8 mph
1200
84°F
W
8 mph
8 mph
1500
84°F
SW
7 mph
7 mph
1800
82°F
SW
6 mph
6 mph
2100
84°F
SW
12 mph
12 mph
September 20, sunday
0000
84°F
W
11 mph
11 mph
0300
84°F
NW
7 mph
7 mph
