September weather forecastCarbondale, IL
September
Weather in September
September brings the onset of fall to Carbondale, Illinois, with temperatures dropping from 60.3°F (15.7°C) to 80.4°F (26.9°C). The decrease in rainfall to an average of 1.85" (47mm) marks the driest month of the year. Less cloud cover coupled with increased visibility may lead to more sunshine and clear skies. Despite the wind becoming more prominent again, the UV index dips. Therefore, this month is an opportune time to enjoy the outdoors while the summer warmth lingers.Temperature
September's arrival subtly correlates with a reduction in the average high-temperature, down from 85.8°F (29.9°C) in August to a still moderately hot 80.4°F (26.9°C). An average low-temperature of 60.3°F (15.7°C) marks the nights in Carbondale throughout September.Humidity
In September, the average relative humidity is 73%.Rainfall
September is the month with the least rainfall in Carbondale. Rain falls for 12.7 days and accumulates 1.85" (47mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
In September, the average length of the day in Carbondale is 12h and 25min.On the first day of September in Carbondale, sunrise is at 6:27 am and sunset at 7:25 pm. On the last day of the month, sunrise is at 6:52 am and sunset at 6:40 pm CDT.
Sunshine
In Carbondale, the average sunshine in September is 9.5h.UV index
The average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a moderate threat to health from unprotected exposure to Sun's UV rays for the average person.Note: The maximum UV index, 5 during September, leads to the following recommendations:
Be vigilant - Suggestions to stave off sun damage are provided. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Carbondale, IL
- Average high temperature in September: 80.4°F
The warmest month (with the highest average high temperature) is July (87.4°F).
The month with the lowest average high temperature is January (39.6°F).
- Average low temperature in September: 60.3°F
The month with the highest average low temperature is July (68.7°F).
The coldest month (with the lowest average low temperature) is January (26.2°F).
Average pressure in September
Carbondale, 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 (29.93"Hg).
Average wind speed in September
Carbondale, IL
- Average wind speed in September: 6.2mph
The windiest month (with the highest average wind speed) is January (9.4mph).
The calmest month (with the lowest average wind speed) is August (5.6mph).
Average humidity in September
Carbondale, IL
- Average humidity in September: 73%
The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Carbondale, IL
- Average rainfall in September: 1.85"
The wettest month (with the highest rainfall) is April (4.49").
The driest month (with the least rainfall) is September (1.85").
Average rainfall days in September
Carbondale, IL
- Average rainfall days in September: 12.7 days
The month with the highest number of rainy days is May (17.1 days).
The month with the least rainy days is January (9.4 days).
Average snowfall in September
Carbondale, IL
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.73").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Carbondale, IL
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are January and February (4.8 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
Carbondale, IL
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 9h and 30min
The month with the most sunshine is June (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).
Average sunshine days in September
Carbondale, IL
- Average sunshine days in September: 16 days
The month with the most sunshine days is October (18.5 days).
The month with the least sunshine days is May (11.3 days).
Average UV index in September
Carbondale, 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
Carbondale, IL
- Average cloud cover in September: 28
The month with the most cloud cover is February (Cloud cover 50).
The months with the least cloud cover are June and August (Cloud cover 27).
Average visibility in September
Carbondale, 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).
