September weather forecastChatsworth, IL
September
Weather in September
The first month of the autumn, September, is still a warm month in Chatsworth, Illinois, with an average temperature varying between 75.7°F (24.3°C) and 57.2°F (14°C).Temperature
The commencement of September introduces an average high-temperature of a still moderately hot 75.7°F (24.3°C), closely mirroring the preceding month. The nights of September anticipate an average low-temperature of 57.2°F (14°C).Humidity
The average relative humidity in September is 76%.Rainfall
In September, the rain falls for 10.5 days. Throughout September, 1.18" (30mm) of precipitation is accumulated. Throughout the year, there are 130.5 rainfall days, and 17.44" (443mm) of precipitation is accumulated.Snowfall
In Chatsworth, snow does not fall in May through September.Daylight
In Chatsworth, the average length of the day in September is 12h and 27min.On the first day of the month, sunrise is at 6:20 am and sunset at 7:24 pm. On the last day of September, sunrise is at 6:49 am and sunset at 6:36 pm CDT.
Sunshine
The average sunshine in September is 8.9h.UV index
In Chatsworth, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for average individuals.Note: An average UV index of 4 in September transforms into this advice:
Exercise prevention - Warding off sunburn is urged. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Chatsworth, IL
- Average high temperature in September: 75.7°F
The warmest month (with the highest average high temperature) is July (80.8°F).
The month with the lowest average high temperature is January (30.6°F).
- Average low temperature in September: 57.2°F
The month with the highest average low temperature is July (64.6°F).
The coldest month (with the lowest average low temperature) is January (18.5°F).
Average pressure in September
Chatsworth, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Chatsworth, IL
- Average wind speed in September: 7.6mph
The windiest month (with the highest average wind speed) is January (10.8mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in September
Chatsworth, IL
- Average humidity in September: 76%
The month with the highest relative humidity is July (86%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Chatsworth, IL
- Average rainfall in September: 1.18"
The wettest month (with the highest rainfall) is May (2.56").
The driest month (with the least rainfall) is January (0.79").
Average rainfall days in September
Chatsworth, IL
- Average rainfall days in September: 10.5 days
The month with the highest number of rainy days is May (17 days).
The months with the least rainy days are January and February (5 days).
Average snowfall in September
Chatsworth, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (2.09").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Chatsworth, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.6 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
Chatsworth, IL
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 8h and 54min
The month with the most sunshine is June (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in September
Chatsworth, IL
- Average sunshine days in September: 17.2 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is July (11.4 days).
Average UV index in September
Chatsworth, IL
- Average UV index in September: 4
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Chatsworth, IL
- Average cloud cover in September: 32
The month with the most cloud cover is January (Cloud cover 59).
The month with the least cloud cover is September (Cloud cover 32).
Average visibility in September
Chatsworth, IL
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
