September weather forecastAtwater, IL
September
Weather in September
September, the first month of the autumn in Atwater, is still a warm month, with an average temperature ranging between min 59.4°F (15.2°C) and max 77.7°F (25.4°C).Temperature
Atwater in September witnesses an average high-temperature of a still warm 77.7°F (25.4°C), indicating a slight variation from August's 82.2°F (27.9°C). Atwater, during the month of September, experiences an average low-temperature of 59.4°F (15.2°C).Humidity
The average relative humidity in September is 75%.Rainfall
In Atwater, in September, it is raining for 13.2 days, with typically 2.4" (61mm) of accumulated precipitation. In Atwater, during the entire year, the rain falls for 151.5 days and collects up to 31.3" (795mm) of precipitation.Snowfall
May through October are months without snowfall.Daylight
In September, the average length of the day is 12h and 26min.On the first day of the month, sunrise is at 6:28 am and sunset at 7:29 pm. On the last day of September, in Atwater, sunrise is at 6:54 am and sunset at 6:42 pm CDT.
Sunshine
In September, the average sunshine is 9.2h.UV index
The average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.Note: In September, the maximum UV index of 5 transforms into these recommendations:
Be cautious. Those with fair skin can be subjected to burns in fewer than 30 minutes. For skin protection, it's recommended to minimize Sun exposure during its peak hours around midday. Opt for tightly woven and loose clothing to enhance protection from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Atwater, IL
- Average high temperature in September: 77.7°F
The warmest month (with the highest average high temperature) is July (83.3°F).
The month with the lowest average high temperature is January (34.2°F).
- Average low temperature in September: 59.4°F
The month with the highest average low temperature is July (66.7°F).
The coldest month (with the lowest average low temperature) is January (22.3°F).
Average pressure in September
Atwater, IL
- Average pressure in September: 30.02"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Atwater, IL
- Average wind speed in September: 6.8mph
The windiest month (with the highest average wind speed) is January (10.3mph).
The calmest months (with the lowest average wind speed) are July and August (6mph).
Average humidity in September
Atwater, IL
- Average humidity in September: 75%
The month with the highest relative humidity is July (82%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Atwater, IL
- Average rainfall in September: 2.4"
The wettest month (with the highest rainfall) is June (3.86").
The driest month (with the least rainfall) is December (1.73").
Average rainfall days in September
Atwater, IL
- Average rainfall days in September: 13.2 days
The month with the highest number of rainy days is May (17.8 days).
The month with the least rainy days is January (7.4 days).
Average snowfall in September
Atwater, IL
- Average snowfall in September: 0"
The month with the highest snowfall is February (3.19").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Atwater, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (8.5 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
Atwater, IL
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in September: 9h and 12min
The month with the most sunshine is June (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in September
Atwater, IL
- Average sunshine days in September: 14.7 days
The month with the most sunshine days is October (18.5 days).
The month with the least sunshine days is May (10.6 days).
Average UV index in September
Atwater, IL
- Average UV index in September: 5
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Atwater, IL
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 53).
The months with the least cloud cover are June, July, August and September (Cloud cover 30).
Average visibility in September
Atwater, 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).





