September weather forecastGlen Ellyn, IL
September
Weather in September
The first month of the autumn, September, is still a warm month in Glen Ellyn, Illinois, with an average temperature fluctuating between 57.4°F (14.1°C) and 73.6°F (23.1°C).Temperature
September ushers in a minor alteration in Glen Ellyn's climate, with the average high-temperature moving from August's 80.4°F (26.9°C) to a still warm 73.6°F (23.1°C). In September, Glen Ellyn reports a consistent average low-temperature of 57.4°F (14.1°C) during the nights.Humidity
The average relative humidity in September in Glen Ellyn is 76%.Rainfall
In Glen Ellyn, in September, it is raining for 14.6 days, with typically 2.48" (63mm) of accumulated precipitation. Throughout the year, there are 164.3 rainfall days, and 33.78" (858mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in September is 12h and 28min.On the first day of September, sunrise is at 6:18 am and sunset at 7:25 pm. On the last day of the month, sunrise is at 6:48 am and sunset at 6:35 pm CDT.
Sunshine
In September, the average sunshine in Glen Ellyn is 8.8h.UV index
The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV rays for the average person.Note: In September, the maximum UV index of 4 transforms into these recommendations:
Act with care - The suggestion to avoid sunburn is emphasized. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Glen Ellyn, IL
- Average high temperature in September: 73.6°F
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (28°F).
- Average low temperature in September: 57.4°F
The month with the highest average low temperature is July (65.3°F).
The coldest month (with the lowest average low temperature) is January (16.7°F).
Average pressure in September
Glen Ellyn, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Glen Ellyn, IL
- Average wind speed in September: 7mph
The windiest month (with the highest average wind speed) is January (9.8mph).
The calmest month (with the lowest average wind speed) is August (6mph).
Average humidity in September
Glen Ellyn, IL
- Average humidity in September: 76%
The months with the highest relative humidity are January and February (83%).
The month with the lowest relative humidity is October (73%).
Average rainfall in September
Glen Ellyn, IL
- Average rainfall in September: 2.48"
The wettest month (with the highest rainfall) is May (4.45").
The driest months (with the least rainfall) are November and December (1.65").
Average rainfall days in September
Glen Ellyn, IL
- Average rainfall days in September: 14.6 days
The month with the highest number of rainy days is July (20.1 days).
The month with the least rainy days is February (5.8 days).
Average snowfall in September
Glen Ellyn, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (5.87").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Glen Ellyn, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (13.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Glen Ellyn, 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 12min).
- Average sunshine in September: 8h and 48min
The month with the most sunshine is August (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in September
Glen Ellyn, IL
- Average sunshine days in September: 12.3 days
The month with the most sunshine days is November (16.1 days).
The month with the least sunshine days is July (8.2 days).
Average UV index in September
Glen Ellyn, IL
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in September
Glen Ellyn, IL
- Average cloud cover in September: 32
The month with the most cloud cover is January (Cloud cover 61).
The months with the least cloud cover are August and September (Cloud cover 32).
Average visibility in September
Glen Ellyn, IL
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January and February (5mi).
