September weather forecastRoscoe, IL
September
Weather in September
The first month of the autumn, September, is still a pleasant month in Roscoe, Illinois, with an average temperature ranging between min 53.8°F (12.1°C) and max 72.3°F (22.4°C).Temperature
September brings a minor shift in the average high-temperature, adjusting from a warm 78.1°F (25.6°C) in August to an agreeable 72.3°F (22.4°C). Throughout the month of September, Roscoe reports a steady low-temperature average of 53.8°F (12.1°C).Humidity
In September, the average relative humidity is 80%.Rainfall
In Roscoe, during September, the rain falls for 10.1 days and regularly aggregates up to 1.02" (26mm) of precipitation. Throughout the year, there are 123.8 rainfall days, and 14.49" (368mm) of precipitation is accumulated.Snowfall
May through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 28min.On the first day of the month, sunrise is at 6:22 am and sunset at 7:29 pm. On the last day of September, sunrise is at 6:52 am and sunset at 6:38 pm CDT.
Sunshine
In September, the average sunshine is 8.6h.UV index
In Roscoe, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for average individuals.Note: An average maximum UV index of 4 in September leads to these recommendations:
Safety measures are advised. Light-skinned individuals may experience burns in under half an hour. Direct Sun exposure should be minimized especially during midday when radiation is most intense. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Roscoe, IL
- Average high temperature in September: 72.3°F
The warmest month (with the highest average high temperature) is July (79.9°F).
The month with the lowest average high temperature is January (25.5°F).
- Average low temperature in September: 53.8°F
The month with the highest average low temperature is July (63°F).
The coldest month (with the lowest average low temperature) is January (13.5°F).
Average pressure in September
Roscoe, IL
- Average pressure in September: 30.03"Hg
The months with the highest atmospheric pressure are January and February (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Roscoe, IL
- Average wind speed in September: 7.3mph
The windiest month (with the highest average wind speed) is April (10.1mph).
The calmest month (with the lowest average wind speed) is August (6.3mph).
Average humidity in September
Roscoe, IL
- Average humidity in September: 80%
The month with the highest relative humidity is January (86%).
The month with the lowest relative humidity is October (75%).
Average rainfall in September
Roscoe, IL
- Average rainfall in September: 1.02"
The wettest month (with the highest rainfall) is June (2.2").
The driest month (with the least rainfall) is February (0.51").
Average rainfall days in September
Roscoe, IL
- Average rainfall days in September: 10.1 days
The month with the highest number of rainy days is May (16.5 days).
The month with the least rainy days is January (3.8 days).
Average snowfall in September
Roscoe, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (1.93").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Roscoe, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.3 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
Roscoe, IL
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 8h and 36min
The month with the most sunshine is July (Average sunshine: 9h and 42min).
The months with the least sunshine are January and February (Average sunshine: 3h and 36min).
Average sunshine days in September
Roscoe, IL
- Average sunshine days in September: 18.1 days
The month with the most sunshine days is November (19.7 days).
The month with the least sunshine days is June (11.4 days).
Average UV index in September
Roscoe, IL
- Average UV index in September: 4
The month with the highest UV index is June (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Roscoe, IL
- Average cloud cover in September: 34
The month with the most cloud cover is January (Cloud cover 63).
The month with the least cloud cover is September (Cloud cover 34).
Average visibility in September
Roscoe, IL
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are January, July and August (5mi).





