September weather forecastBull Valley, IL
September
Weather in September
September, the first month of the autumn in Bull Valley, is also an agreeable month, with an average temperature varying between 55°F (12.8°C) and 72.3°F (22.4°C).Temperature
September's arrival coincides with a soft drop in the average high-temperature, subtly decreasing from August's moderately hot 78.1°F (25.6°C) to a pleasant 72.3°F (22.4°C). During September, Bull Valley observes a consistent average nighttime temperature of 55°F (12.8°C).Humidity
In September, the average relative humidity is 80%.Rainfall
In Bull Valley, in September, during 13.5 rainfall days, 2.09" (53mm) of precipitation is typically accumulated. In Bull Valley, during the entire year, the rain falls for 152.4 days and collects up to 28.07" (713mm) of precipitation.Snowfall
In Bull Valley, snow does not fall in June through September.Daylight
In Bull Valley, 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 7:26 pm. On the last day of September, sunrise is at 6:50 am and sunset at 6:36 pm CDT.
Sunshine
The average sunshine in September is 8.9h.UV index
In September, the average daily maximum UV index is 4. A UV Index of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV rays for the average person.Note: An average UV index of 4 in September transforms into this advice:
Prioritize safety - Recommendations to avert sunburn are shared. Avoiding direct sunlight during midday hours helps reduce the risk from intense UV radiation. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Bull Valley, IL
- Average high temperature in September: 72.3°F
The warmest month (with the highest average high temperature) is July (79.7°F).
The month with the lowest average high temperature is January (26.6°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
Bull Valley, 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
Bull Valley, IL
- Average wind speed in September: 7.3mph
The windiest month (with the highest average wind speed) is January (10mph).
The calmest month (with the lowest average wind speed) is August (6.2mph).
Average humidity in September
Bull Valley, IL
- Average humidity in September: 80%
The months with the highest relative humidity are January and February (85%).
The month with the lowest relative humidity is October (76%).
Average rainfall in September
Bull Valley, IL
- Average rainfall in September: 2.09"
The wettest month (with the highest rainfall) is June (3.58").
The driest month (with the least rainfall) is December (1.34").
Average rainfall days in September
Bull Valley, IL
- Average rainfall days in September: 13.5 days
The month with the highest number of rainy days is July (18.3 days).
The month with the least rainy days is February (4.9 days).
Average snowfall in September
Bull Valley, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (5.16").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Bull Valley, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (13.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Bull Valley, 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: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in September
Bull Valley, IL
- Average sunshine days in September: 14.3 days
The month with the most sunshine days is November (16 days).
The month with the least sunshine days is June (10.2 days).
Average UV index in September
Bull Valley, IL
- Average UV index in September: 4
The month with the highest UV index is August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Bull Valley, IL
- Average cloud cover in September: 31
The month with the most cloud cover is January (Cloud cover 62).
The months with the least cloud cover are August and September (Cloud cover 31).
Average visibility in September
Bull Valley, 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).





