September weather forecast
Altoona, FL

The first month of the autumn, September, is still a tropical month in Altoona, Florida, with an average temperature varying between 88.5°F (31.4°C) and 73.2°F (22.9°C).

Temperature

September brings an average high-temperature of a still hot 88.5°F (31.4°C), nearly identical to the preceding month. In Altoona, September nights witness a steady temperature drop to an agreeable 73.2°F (22.9°C).

Heat index

The heat index value during September is computed to be a blisteringly hot 105.8°F (41°C). Take extra safety measures to prevent heat exhaustion and heat cramps. Heatstroke could follow lengthy activity.
It is emphasized that the heat index's values are meant for shaded zones with mild winds. Direct sunshine exposure could raise heat index values by as much as 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', is an indicator that blends the effects of temperature and humidity to depict perceived warmth. The influence of weather is personal, differing among individuals based on variations in body mass, stature, and the degree of physical exertion. Direct sunlight exposure should be noted as it has the potential to increase the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly meaningful for babies and toddlers. 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.
Perspiration is the body's default response to elevated temperatures, as it promotes the evaporation of sweat to achieve cooling. Excessive relative humidity disturbs the body's typical cooling process by reducing evaporation, leading to a decrease in body cooling rate and an increase in the sensation of warmth. As the body gains more heat than it can dissipate, there's a risk of increasing temperatures and resultant overheating.

Humidity

July through September, with an average relative humidity of 78%, are the most humid months.

Rainfall

In Altoona, in September, it is raining for 22.3 days, with typically 4.02" (102mm) of accumulated precipitation. Throughout the year, in Altoona, there are 193.1 rainfall days, and 35.71" (907mm) of precipitation is accumulated.

Daylight

The average length of the day in September is 12h and 19min.
On the first day of the month, sunrise is at 7:04 am and sunset at 7:47 pm. On the last day of September, in Altoona, sunrise is at 7:19 am and sunset at 7:13 pm EDT.

Sunshine

In Altoona, the average sunshine in September is 8.7h.

UV index

In Altoona, the average daily maximum UV index in September is 6. A UV Index of 6 to 7 symbolizes a high health hazard from exposure to the Sun's UV rays for the ordinary person.
Note: A maximum UV index of 6 in September translates into the following recommendations:
Incorporate safeguards and honour sun safety principles. Protection from skin and eye damage is obligatory. Stay in the shade and limit sun exposure from 10 a.m. to 4 p.m., when UV radiation is most potent. Keep in mind that shade structures like parasols or canopies do not offer full protection. Tightly woven clothing, when worn loosely, shields effectively against the Sun.