Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
As August transitions into September, the average high-temperature rests at a still hot 87.1°F (30.6°C), maintaining a close resemblance to the previous month. Dismal Key documents an average low-temperature of 78.4°F (25.8°C) for the nights of September.Heat index
In September, the heat index is computed to be a torrid 100.4°F (38°C). Special measures are necessary to avoid heat cramps and heat exhaustion. Persistent activity could result in heatstroke.It is crucial to understand that heat index figures are for shade and gentle wind conditions. Direct exposure to sunshine could lead to a heat index increase by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'feels like', is achieved by amalgamating air temperature with the relative humidity readings. Elements such as metabolic variations, being pregnant, and physical activity can impact one's weather perception. Given the impact of direct sunlight, it's noteworthy that the felt temperature can rise by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold particular importance for children. Youths are typically more endangered than adults since they usually sweat less. Their larger skin surface concerning their smaller bodies and higher heat production due to activity further adds to their vulnerability.
By perspiring, the human body can shed its excessive warmth since evaporated sweat cools it off. In circumstances of high air temperature and humidity (high heat index), the body's perspiration is restricted, heightening the feeling of warmth. With body temperatures on the rise, inefficient heat shedding can lead to dehydration and its associated complications.
Humidity
In September, the average relative humidity in Dismal Key is 75%.Rainfall
In Dismal Key, during September, the rain falls for 21.5 days and regularly aggregates up to 2.4" (61mm) of precipitation. In Dismal Key, during the entire year, the rain falls for 162.1 days and collects up to 21.69" (551mm) of precipitation.Daylight
In Dismal Key, the average length of the day in September is 12h and 18min.On the first day of the month, sunrise is at 7:06 am and sunset at 7:45 pm. On the last day of September, sunrise is at 7:18 am and sunset at 7:13 pm EDT.
Sunshine
In September, the average sunshine is 9.2h.UV index
The months with the highest UV index are May through September, with an average maximum UV index of 7. A UV Index of 6 to 7 symbolizes a high health risk from exposure to the Sun's UV radiation for average individuals.Note: In September, the average maximum UV index of 7 translates into the following recommendations:
Adhere to precautions and respect sun safety doctrines. Avoiding sunburn is vital. Avoid direct Sun exposure and seek shade from 10 a.m. to 4 p.m., the period of highest UV radiation. Remember, however, that not all shade structures offer full protection. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is September?
What is the average humidity in September?
How many days does it rain in September?
How many hours of daylight does Dismal Key have in September?
What time are sunrise and sunset in September?
How long on average sun shines in September?
What are the months with the highest UV index?
What is the UV index reading in September?
Average temperature in September
Dismal Key, FL
- Average high temperature in September: 87.1°F
The warmest month (with the highest average high temperature) is August (88.3°F).
The month with the lowest average high temperature is January (71.6°F).
- Average low temperature in September: 78.4°F
The month with the highest average low temperature is August (80.2°F).
The coldest month (with the lowest average low temperature) is January (59.5°F).
Average pressure in September
Dismal Key, FL
- Average pressure in September: 29.94"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is September (29.94"Hg).
Average wind speed in September
Dismal Key, FL
- Average wind speed in September: 7mph
The windiest month (with the highest average wind speed) is November (9.2mph).
The calmest month (with the lowest average wind speed) is July (6.2mph).
Average humidity in September
Dismal Key, FL
- Average humidity in September: 75%
The month with the highest relative humidity is December (76%).
The month with the lowest relative humidity is March (72%).
Average rainfall in September
Dismal Key, FL
- Average rainfall in September: 2.4"
The wettest month (with the highest rainfall) is August (4.29").
The driest month (with the least rainfall) is March (0.63").
Average rainfall days in September
Dismal Key, FL
- Average rainfall days in September: 21.5 days
The month with the highest number of rainy days is August (22.4 days).
The month with the least rainy days is February (7 days).
Average daylight in September /
Average sunshine in September
Dismal Key, FL
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 13h and 42min).
The month with the shortest days is December (Average daylight: 10h and 36min).
- Average sunshine in September: 9h and 1min
The months with the most sunshine are May and July (Average sunshine: 11h and 6min).
The month with the least sunshine is December (Average sunshine: 6h and 42min).
Average sunshine days in September
Dismal Key, FL
- Average sunshine days in September: 7.1 days
The month with the most sunshine days is January (21.8 days).
The month with the least sunshine days is August (6.8 days).
Average UV index in September
Dismal Key, FL
- Average UV index in September: 7
The months with the highest UV index are May, June, July, August and September (UV index 7).
The months with the lowest UV index are January and February (UV index 5).
Average cloud cover in September
Dismal Key, FL
- Average cloud cover in September: 27
The month with the most cloud cover is January (Cloud cover 28).
The months with the least cloud cover are March and April (Cloud cover 22).
Average visibility in September
Dismal Key, FL
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Dismal Key, Florida, USA
Weather forecast for your location
2. Allow the app to use your location