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 snowfall 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
With the onset of September, the average high-temperature subtly recedes from August's very hot 99°F (37.2°C) to a tropical 92.7°F (33.7°C). During September, Alton sees a mean low-temperature of 77.2°F (25.1°C).Heat index
For most parts of September, the heat index is calculated to be a scorching 109.4°F (43°C). Careful: Heat exhaustion and heat cramps are anticipated. With ongoing exertion, heatstroke becomes a possibility.The metrics for the heat index are tailored for both shady environments and light winds. Direct sunlight has the potential to heighten heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is an estimation of the warmth sensation when considering humidity levels. The impact of weather is personal, differing among a variety of people based on differences in body mass, height, and the level of physical exertion. Keep it in mind, direct sunlight can augment the heat you experience, possibly pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly important for children. Young ones regularly neglect the requirement for rest and fluid replenishment. Thirst is a late stage of dehydration - so, it is necessary to keep hydrated, particularly during extended periods of physical exertion.
Perspiration, which is the evaporation of sweat, is a primary way the human body manages and dispels excessive warmth. Augmented relative humidity impedes typical body cooling mechanisms by lowering the evaporation rate, resulting in decreased body cooling and an amplified perception of heat. With body temperatures on the rise, inefficient heat shedding can lead to dehydration and its associated complications.
Humidity
In September, the average relative humidity is 64%.Rainfall
In Alton, Texas, in September, during 11.3 rainfall days, 0.47" (12mm) of precipitation is typically accumulated. In Alton, during the entire year, the rain falls for 68.7 days and collects up to 3.62" (92mm) of precipitation.Snowfall
March through December are months without snowfall in Alton.Daylight
In September, the average length of the day in Alton is 12h and 18min.On the first day of the month, sunrise is at 7:13 am and sunset at 7:52 pm. On the last day of September, in Alton, sunrise is at 7:25 am and sunset at 7:20 pm CDT.
Sunshine
In September, the average sunshine in Alton is 8.6h.UV index
In September, the average daily maximum UV index is 7. A UV Index of 6 to 7 symbolizes a high health hazard from unsafe exposure to UV radiation for average individuals.Note: In September, the maximum UV index of 7 translates into these guidelines:
Prevent overexposure. Protection from the sun's harmful effects is needed. It's important to stay in the shade and limit exposure to the sun from 10 a.m. to 4 p.m., when UV radiation is most intense, although remember that shade structures may not provide full sun protection. Safeguard your eyes, ears, and face from sun rays with the aid of a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is it in Alton in September?
What is the average humidity in September in Alton?
How many days does it rain in September in Alton?
When it does not snow in Alton?
What is the average length of the day in September in Alton?
When is the sunrise / sunset in September in Alton?
How long on average sun shines in September in Alton?
What is the UV index intensity in September in Alton?
Average temperature in September
Alton, TX
- Average high temperature in September: 92.7°F
The warmest month (with the highest average high temperature) is August (99°F).
The month with the lowest average high temperature is January (69.4°F).
- Average low temperature in September: 77.2°F
The month with the highest average low temperature is August (79.9°F).
The coldest month (with the lowest average low temperature) is January (53.2°F).
Average pressure in September
Alton, TX
- Average pressure in September: 29.91"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The months with the lowest atmospheric pressure are May and June (29.87"Hg).
Average wind speed in September
Alton, TX
- Average wind speed in September: 9.3mph
The windiest months (with the highest average wind speed) are May and July (12.9mph).
The calmest month (with the lowest average wind speed) is September (9.3mph).
Average humidity in September
Alton, TX
- Average humidity in September: 64%
The months with the highest relative humidity are May and December (67%).
The month with the lowest relative humidity is August (58%).
Average rainfall in September
Alton, TX
- Average rainfall in September: 0.47"
The wettest month (with the highest rainfall) is July (0.71").
The driest months (with the least rainfall) are February and December (0.12").
Average rainfall days in September
Alton, TX
- Average rainfall days in September: 11.3 days
The month with the highest number of rainy days is September (11.3 days).
The month with the least rainy days is February (2.9 days).
Average snowfall days in September
Alton, TX
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are January and February (0.1 days).
The months with the least snowfall days are March, April, May, June, July, August, September, October, November and December (0 days).
Average daylight in September /
Average sunshine in September
Alton, TX
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 13h and 48min).
The month with the shortest days is December (Average daylight: 10h and 30min).
- Average sunshine in September: 8h and 4min
The month with the most sunshine is July (Average sunshine: 11h and 24min).
The month with the least sunshine is December (Average sunshine: 5h and 36min).
Average sunshine days in September
Alton, TX
- Average sunshine days in September: 15.6 days
The month with the most sunshine days is March (24.9 days).
The month with the least sunshine days is September (15.6 days).
Average UV index in September
Alton, TX
- Average UV index in September: 7
The months with the highest UV index are July and August (UV index 8).
The month with the lowest UV index is December (UV index 4).
Average cloud cover in September
Alton, TX
- Average cloud cover in September: 30
The month with the most cloud cover is December (Cloud cover 38).
The month with the least cloud cover is August (Cloud cover 17).
Average visibility in September
Alton, TX
- 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).
Alton, Texas, USA
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