Key West Weather: September
 |
Average Day Temperature: | 89.6°F |
|
Average Night Temperature: | 86.2°F |
|
Sea Water Temperature: | 90.2°F |
|
Number of Sunny Days: | 10 days |
| Sunshine Hours: | 11.9 - 12.6 hours | |
|
Number of Rainy Days: | 6 days |
| Precipitation Totals: | 4.6 in | |
| detailed information | ||
forecast
| Key West |
Temperature
| Key West |
Air Temperature in September, °F
The highest day temperature in September 2026 was 92°F. The lowest night temperature was 84°F. The average values for day and night temperatures during September were 87.4°F и 87.9°F respectivly.
Key West Water Sea Temperature in September, °F
The average sea surface temperature in September 2026 for Key West was 92.0°F. The maximum and minimum values were 89.8°F and 93.8°F respectively.
Most of the days in September are cloudy but you can also expect sunny or gloomy days.
Precipitation Totals in September, in
Precipitation total in September for Key West is 4.6 in. It makes september the most rainy month of the year.
The average wind speed in September is 9.7 mph. It makes September the most windless month of the year for Key West.
We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Key West in September is 7.1 hours.
Key West on the Weather Map
| Boston |  |
+58 |
| Chicago | |
+60 |
| Hawaii |  |
+82 |
| Houston |  |
+84 |
| Las Vegas |  |
+92 |
| Los Angeles | |
+102 |
| Maui |  |
+74 |
| Miami | |
+88 |
| Myrtle Beach | |
+70 |
| New York | |
+62 |
| San Diego | |
+84 |
| San Francisco | |
+66 |
| Santa Monica | |
+94 |
| Sarasota | |
+84 |
| Washington | |
+64 |
| 2100 |  |
88°F | W 6 mph |
| 0000 |  |
86°F | W 8 mph |
| 0300 |  |
86°F | W 8 mph |
| 0600 |  |
86°F | NW 9 mph |
| 0900 | |
86°F | NW 7 mph |
| 1200 |  |
86°F | NW 6 mph |
| 1500 | |
86°F | NW 6 mph |
| 1800 |  |
86°F | NW 4 mph |