Weather in Key West, United States in September

So you're interested in going to Key West, United States in September

September is a hot and very rainy time for sunbathing in Key West. September is an excellent month for swimming in Key West with very warm sea temperatures. Consider visiting Key West in the months of March, April, May, December, for the best beach weather. Also consider one of our other suggestions for September.

Temperature in Key West in September

The average maximum temperature in Key West in September is 31°. The average maximum temperature is 32° in the previous month and 30° in the next month.

The average temperature in Key West in September is 29°. The average temperature ranges is 30° in the previous month and 27° in the next month.

The average minimum temperature in Key West in September is 26°. The minimum temperature is 27° in the previous month and 25° in the next month.

Sunshine in Key West in September

The average day light hours per day in Key West in September are 12.3 and there are 7.6 hours of sunshine per day on average during September making it a quite sunny month with some cloud cover.

The ultraviolet index in Key West in September is typically 11 during September. An ultraviolet index reading above 11 indicates an extreme risk of harm from unprotected sun exposure. Unprotected skin risks burning in less than 10 minutes. Take all precautions because unprotected skin and eyes can burn in minutes. Tanning will be safest before 10am and after 4pm but only with a good application of sun screen. For those with sensitive skin stay in the shade and wear protective clothing, a wide-brimmed hat, and UV-blocking sunglasses. Generously apply broad spectrum SPF 30+ sunscreen every 2 hours, even on cloudy days. Watch out for relections from water that may increase ultraviolet exposure.

Sea Temperature in Key West in September

The average sea water temperature in Key West in September is 29.5° which is very warm and ideal for relaxing and swimming for the whole day.

Rainfall in Key West in September

The average total rainfall in Key West in September is 217.1cm and on average there are 19 rainy days in September making it a very wet time to visit the beach.

Humidity in Key West in September

The maximum dew point (an indicator of humidity) in Key West in September is 25° which is very uncomfortable and fairly oppressive unless you are on a beach. At night you would most likely require airconditioning. The dew point is 25° in the previous month and 23° in the next month.

The average maximum relative humidity in Key West in September is typically 86.1%. The maximum relative humidity is 81.8% in the previous month and 84.8% in the next month.

The average relative humidity in Key West in September is typically 75.8%. The average relative humidity is 72.3% in the previous month and 74.5% in the next month.

Wind Speed in Key West in September

The average maximum wind speed in Key West in September is typically 29kmh. The average maximum wind speed is 29kmh in the previous month and 29kmh in the next month.

The average wind speed in Key West in September is typically 14kmh. The average wind speed is 14kmh in the previous month and 16kmh in the next month.

The average wind direction in Key West in September is from the East.

Monthly Averages

Suggested Beaches in September

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