September weather forecastCrest Hill, IL
September
Weather in September
September, the first month of the autumn in Crest Hill, is still a warm month, with temperature in the range of an average low of 56.7°F (13.7°C) and an average high of 74.7°F (23.7°C).Temperature
The onset of September entails a subtle temperature shift, as the average high-temperature eases from a warm 80.1°F (26.7°C) in August to a still moderately hot 74.7°F (23.7°C). Throughout the nights in September, Crest Hill experiences an average low-temperature of 56.7°F (13.7°C).Humidity
The average relative humidity in September is 78%.Rainfall
In Crest Hill, in September, it is raining for 12.5 days, with typically 2.48" (63mm) of accumulated precipitation. Throughout the year, there are 153.6 rainfall days, and 32.72" (831mm) of precipitation is accumulated.Snowfall
May through October are months without snowfall.Daylight
In Crest Hill, the average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:19 am and sunset at 7:25 pm. On the last day of September, sunrise is at 6:48 am and sunset at 6:35 pm CDT.
Sunshine
In Crest Hill, the average sunshine in September is 8.5h.UV index
In September, the average daily maximum UV index is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for ordinary individuals.Note: In September, the average maximum UV index of 4 translates into the following recommendations:
Be mindful. Individuals with a lighter skin tone may suffer burns in less than 30 minutes. Midday is when the Sun's radiation is strongest; avoid prolonged exposure during this time. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Crest Hill, IL
- Average high temperature in September: 74.7°F
The warmest month (with the highest average high temperature) is July (81.3°F).
The month with the lowest average high temperature is January (29.3°F).
- Average low temperature in September: 56.7°F
The month with the highest average low temperature is July (64.8°F).
The coldest month (with the lowest average low temperature) is January (17.4°F).
Average pressure in September
Crest Hill, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Crest Hill, IL
- Average wind speed in September: 6.9mph
The windiest month (with the highest average wind speed) is April (9.7mph).
The calmest month (with the lowest average wind speed) is August (5.9mph).
Average humidity in September
Crest Hill, IL
- Average humidity in September: 78%
The month with the highest relative humidity is February (83%).
The month with the lowest relative humidity is October (73%).
Average rainfall in September
Crest Hill, IL
- Average rainfall in September: 2.48"
The wettest month (with the highest rainfall) is May (4.41").
The driest month (with the least rainfall) is February (1.61").
Average rainfall days in September
Crest Hill, IL
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is July (17.9 days).
The month with the least rainy days is February (5.7 days).
Average snowfall in September
Crest Hill, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.33").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Crest Hill, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (11.9 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
Crest Hill, IL
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in September: 8h and 30min
The month with the most sunshine is August (Average sunshine: 9h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in September
Crest Hill, IL
- Average sunshine days in September: 15 days
The month with the most sunshine days is November (18.1 days).
The month with the least sunshine days is June (10.4 days).
Average UV index in September
Crest Hill, IL
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Crest Hill, IL
- Average cloud cover in September: 34
The month with the most cloud cover is January (Cloud cover 60).
The months with the least cloud cover are August and September (Cloud cover 34).
Average visibility in September
Crest Hill, IL
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are January, February, July and August (5mi).





