September weather forecastSouth Roxana, IL
September
Weather in September
The first month of the autumn, September, is still a warm month in South Roxana, Illinois, with an average temperature ranging between max 78.6°F (25.9°C) and min 59.4°F (15.2°C).Temperature
The shift from August to September coincides with a small decrease in the average high-temperature, down to a still moderately hot 78.6°F (25.9°C) from a warm 84°F (28.9°C). South Roxana's temperature tends to fall to an average low of 59.4°F (15.2°C) during the nights of September.Humidity
The average relative humidity in September is 75%.Rainfall
In South Roxana, in September, during 11.8 rainfall days, 1.69" (43mm) of precipitation is typically accumulated. Throughout the year, in South Roxana, there are 138 rainfall days, and 23.9" (607mm) of precipitation is accumulated.Snowfall
In South Roxana, snow does not fall in May through October.Daylight
In South Roxana, the average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 6:29 am and sunset at 7:30 pm. On the last day of September, sunrise is at 6:55 am and sunset at 6:44 pm CDT.
Sunshine
In September, the average sunshine is 9.3h.UV index
In September, the average daily maximum UV index is 5. A UV Index reading of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV rays for the average person.Note: An average UV index of 5 in September transforms into this advice:
Adopt protective measures - Suggestions to resist sunburn are offered. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. In the presence of strong sunlight, it's crucial to wear sunglasses that ward off UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
South Roxana, IL
- Average high temperature in September: 78.6°F
The warmest month (with the highest average high temperature) is July (85.3°F).
The month with the lowest average high temperature is January (36.1°F).
- Average low temperature in September: 59.4°F
The month with the highest average low temperature is July (67.6°F).
The coldest month (with the lowest average low temperature) is January (23.4°F).
Average pressure in September
South Roxana, IL
- Average pressure in September: 30.02"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
South Roxana, IL
- Average wind speed in September: 6.3mph
The windiest months (with the highest average wind speed) are January and February (9.6mph).
The calmest month (with the lowest average wind speed) is July (5.7mph).
Average humidity in September
South Roxana, IL
- Average humidity in September: 75%
The month with the highest relative humidity is July (80%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
South Roxana, IL
- Average rainfall in September: 1.69"
The wettest month (with the highest rainfall) is May (3.07").
The driest month (with the least rainfall) is February (1.14").
Average rainfall days in September
South Roxana, IL
- Average rainfall days in September: 11.8 days
The month with the highest number of rainy days is May (16.6 days).
The month with the least rainy days is January (5.6 days).
Average snowfall in September
South Roxana, IL
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.61").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
South Roxana, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (6 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
South Roxana, IL
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in September: 9h and 18min
The month with the most sunshine is June (Average sunshine: 10h and 24min).
The months with the least sunshine are January and February (Average sunshine: 4h and 30min).
Average sunshine days in September
South Roxana, IL
- Average sunshine days in September: 15.7 days
The month with the most sunshine days is December (20.4 days).
The month with the least sunshine days is July (12.3 days).
Average UV index in September
South Roxana, IL
- Average UV index in September: 5
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
South Roxana, IL
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 51).
The months with the least cloud cover are June, July and August (Cloud cover 29).
Average visibility in September
South Roxana, IL
- 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).
