September weather forecast
Dismal Key, FL

The first month of the autumn, September, is still a hot month in Dismal Key, Florida, with temperature in the range of an average high of 87.1°F (30.6°C) and an average low of 78.4°F (25.8°C).

Temperature

At the start of September, Dismal Key's average high-temperature reaches a still tropical 87.1°F (30.6°C), subtly different from the preceding month. Recording a slight decline in temperature during the nights, Dismal Key's September temperatures average at a moderately hot 78.4°F (25.8°C).

Heat index

September's mean heat index is evaluated at a fiery hot 100.4°F (38°C). Undertake enhanced precautions, heat exhaustion and heat cramps are possible risks. Continuous activity could trigger heatstroke.
Take note of the fact that heat index values are based on shaded circumstances with light airflows. Exposure to direct sunshine can increase heat index values by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is a fusion of air temperature and moisture levels to demonstrate the sensation of heat. Factors such as metabolic variation, pregnancy, and physical activity play a role in one's impression of weather. When in direct sunlight, one should be cautious as it can raise the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly important for children. Youngsters are usually more at risk than adults, considering they sweat less. Additionally, their high skin surface area compared to their little bodies and their high heat production due to activity increases their risk.
When faced with excessive heat, the human body begins to perspire, utilizing the cooling benefits of sweat evaporation. When the relative humidity is high, the evaporation rate is reduced. The warmth is removed from the body at a lower rate, causing the body to retain more heat than it would in dry air. When the body is unable to balance heat gain, its temperature elevates, which may induce thermal illnesses.

Humidity

In Dismal Key, Florida, the average relative humidity in September is 75%.

Rainfall

In September, the rain falls for 21.5 days. Throughout September, 2.4" (61mm) of precipitation is accumulated. Throughout the year, there are 162.1 rainfall days, and 21.69" (551mm) of precipitation is accumulated.

Daylight

In Dismal Key, Florida, the average length of the day in September is 12h and 18min.
On the first day of September, sunrise is at 7:06 am and sunset at 7:45 pm. On the last day of the month, sunrise is at 7:18 am and sunset at 7:13 pm EDT.

Sunshine

In Dismal Key, Florida, the average sunshine in September 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 value of 6 to 7 symbolizes a high health vulnerability from exposure to the Sun's UV rays for average individuals.
Note: In September, the maximum UV index of 7 suggests this advice:
Stay clear of intense sun exposure. Solar protection is of utmost significance. Limit your direct sun exposure, especially between 10 a.m. and 4 p.m., when UV radiation is strongest. Shade structures might not provide complete sun protection. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses.