September weather forecastDurham, IL
September
Weather in September
September, the first month of the autumn in Durham, is still a warm month, with an average temperature varying between 76.8°F (24.9°C) and 57.4°F (14.1°C).Temperature
With the arrival of September, Durham experiences a modest decline in average high-temperatures, transitioning from 82.2°F (27.9°C) in August to a still moderately hot 76.8°F (24.9°C). Durham's average low-temperature in September is measured at a mild 57.4°F (14.1°C).Humidity
In Durham, the average relative humidity in September is 75%.Rainfall
In September, the rain falls for 10.2 days. Throughout September, 1.77" (45mm) of precipitation is accumulated. In Durham, Illinois, during the entire year, the rain falls for 127.6 days and collects up to 21.02" (534mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 27min.On the first day of the month, sunrise is at 6:32 am and sunset at 7:35 pm. On the last day of September, sunrise is at 7:00 am and sunset at 6:47 pm CDT.
Sunshine
In September, the average sunshine is 9.3h.UV index
The average daily maximum UV index in September in Durham is 5. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV radiation for ordinary individuals.Note: The daily high UV index of 5 in September translates into this advice:
Make use of precautions - Suggestions to resist sunburn are communicated. It's crucial to reduce time in the direct Sun around mid-day due to the intense solar radiation. For a sun-safe wardrobe, go for clothes that are tightly woven and generously sized.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Durham, IL
- Average high temperature in September: 76.8°F
The warmest month (with the highest average high temperature) is July (82.6°F).
The month with the lowest average high temperature is January (30.9°F).
- Average low temperature in September: 57.4°F
The month with the highest average low temperature is July (66.2°F).
The coldest month (with the lowest average low temperature) is January (18.7°F).
Average pressure in September
Durham, 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 (29.9"Hg).
Average wind speed in September
Durham, IL
- Average wind speed in September: 7.6mph
The windiest month (with the highest average wind speed) is January (10.6mph).
The calmest months (with the lowest average wind speed) are July and August (6.7mph).
Average humidity in September
Durham, IL
- Average humidity in September: 75%
The month with the highest relative humidity is July (83%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Durham, IL
- Average rainfall in September: 1.77"
The wettest month (with the highest rainfall) is May (3.11").
The driest month (with the least rainfall) is January (0.83").
Average rainfall days in September
Durham, IL
- Average rainfall days in September: 10.2 days
The month with the highest number of rainy days is May (17.5 days).
The month with the least rainy days is January (4.3 days).
Average snowfall in September
Durham, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (3.15").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Durham, 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
Durham, IL
- Average daylight in September: 12h and 24min
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: 9h and 18min
The months with the most sunshine are June and July (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in September
Durham, IL
- Average sunshine days in September: 18.4 days
The month with the most sunshine days is December (20 days).
The months with the least sunshine days are May and June (11.8 days).
Average UV index in September
Durham, 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
Durham, IL
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 56).
The months with the least cloud cover are August and September (Cloud cover 30).
Average visibility in September
Durham, 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).





