September weather forecastLake Catherine, IL
September
Weather in September
September, the first month of the autumn in Lake Catherine, is still a pleasant month, with an average temperature fluctuating between 55°F (12.8°C) and 71.6°F (22°C).Temperature
September reveals a small adjustment in temperature, transitioning from an average high of a moderately hot 77.5°F (25.3°C) in August to an agreeable 71.6°F (22°C). The nights of September anticipate an average low-temperature of 55°F (12.8°C).Humidity
In September, the average relative humidity is 80%.Rainfall
In September, the rain falls for 12.5 days. Throughout September, 1.89" (48mm) of precipitation is accumulated. In Lake Catherine, during the entire year, the rain falls for 139.6 days and collects up to 26.18" (665mm) of precipitation.Snowfall
June through September are months without snowfall in Lake Catherine, Illinois.Daylight
The average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:18 am and sunset at 7:26 pm. On the last day of September, sunrise is at 6:49 am and sunset at 6:35 pm CDT.
Sunshine
The average sunshine in September is 8.9h.UV index
In Lake Catherine, the average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for average individuals.Note: During September, 4 as the daily maximum UV index converts into the following advice:
Guard yourself - An obligation to protect skin and eyes from harm exists. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Lake Catherine, IL
- Average high temperature in September: 71.6°F
The warmest month (with the highest average high temperature) is July (79°F).
The month with the lowest average high temperature is January (26.2°F).
- Average low temperature in September: 55°F
The month with the highest average low temperature is July (63.1°F).
The coldest month (with the lowest average low temperature) is January (14.9°F).
Average pressure in September
Lake Catherine, IL
- Average pressure in September: 30.03"Hg
The months with the highest atmospheric pressure are January and February (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Lake Catherine, IL
- Average wind speed in September: 7.5mph
The windiest months (with the highest average wind speed) are January and February (10.3mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in September
Lake Catherine, IL
- Average humidity in September: 80%
The month with the highest relative humidity is January (85%).
The month with the lowest relative humidity is October (76%).
Average rainfall in September
Lake Catherine, IL
- Average rainfall in September: 1.89"
The wettest month (with the highest rainfall) is June (3.54").
The driest month (with the least rainfall) is December (1.06").
Average rainfall days in September
Lake Catherine, IL
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is July (18.5 days).
The month with the least rainy days is February (3.4 days).
Average snowfall in September
Lake Catherine, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.33").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Lake Catherine, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Lake Catherine, 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 54min
The months with the most sunshine are July and August (Average sunshine: 9h and 54min).
The months with the least sunshine are January and February (Average sunshine: 3h and 36min).
Average sunshine days in September
Lake Catherine, IL
- Average sunshine days in September: 14.6 days
The month with the most sunshine days is November (18.7 days).
The month with the least sunshine days is July (9.9 days).
Average UV index in September
Lake Catherine, IL
- Average UV index in September: 4
The months with the highest UV index are May, June, July and August (UV index 5).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Lake Catherine, IL
- Average cloud cover in September: 32
The month with the most cloud cover is January (Cloud cover 63).
The months with the least cloud cover are July, August and September (Cloud cover 32).
Average visibility in September
Lake Catherine, 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).





