September weather forecastDover, IL
September
Weather in September
September, the first month of the autumn in Dover, is also a moderately hot month, with an average temperature fluctuating between 74.7°F (23.7°C) and 56.1°F (13.4°C).Temperature
Dover notes an average high-temperature of a still warm 74.7°F (23.7°C) in September, displaying minor variation from August. Throughout the month of September, Dover observes an average nighttime temperature of 56.1°F (13.4°C).Humidity
In Dover, the average relative humidity in September is 78%.Rainfall
In Dover, in September, during 10.5 rainfall days, 1.22" (31mm) of precipitation is typically accumulated. Throughout the year, in Dover, there are 130 rainfall days, and 17.64" (448mm) of precipitation is accumulated.Snowfall
In Dover, snow does not fall in May through September.Daylight
In September, the average length of the day is 12h and 28min.On the first day of September, sunrise is at 6:24 am and sunset at 7:30 pm. On the last day of the month, sunrise is at 6:54 am and sunset at 6:40 pm CDT.
Sunshine
The average sunshine in September is 8.9h.UV index
The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a moderate threat to health from unsafe exposure to UV radiation for ordinary individuals.Note: A daily maximum UV index of 4 in September translates into the following instructions:
Preventative actions are necessary - The mandate to avoid skin and eye damage is in place. Considering the strength of solar radiation at midday, one should avoid direct Sun exposure. Outfit yourself in sun-safe attire, like long sleeves, pants, a hat, and UV-blocking sunglasses. Consider carefully! The reflective quality of snow can almost double the intensity of the Sun's UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Dover, IL
- Average high temperature in September: 74.7°F
The warmest month (with the highest average high temperature) is July (80.6°F).
The month with the lowest average high temperature is January (28.8°F).
- Average low temperature in September: 56.1°F
The month with the highest average low temperature is July (64.2°F).
The coldest month (with the lowest average low temperature) is January (16.5°F).
Average pressure in September
Dover, 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 (29.91"Hg).
Average wind speed in September
Dover, IL
- Average wind speed in September: 7.6mph
The windiest month (with the highest average wind speed) is April (10.5mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in September
Dover, IL
- Average humidity in September: 78%
The month with the highest relative humidity is July (85%).
The month with the lowest relative humidity is October (72%).
Average rainfall in September
Dover, IL
- Average rainfall in September: 1.22"
The wettest month (with the highest rainfall) is May (2.91").
The driest month (with the least rainfall) is January (0.75").
Average rainfall days in September
Dover, IL
- Average rainfall days in September: 10.5 days
The month with the highest number of rainy days is May (17 days).
The month with the least rainy days is February (4.5 days).
Average snowfall in September
Dover, 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
Dover, IL
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is January (10.4 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Dover, IL
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in September: 8h and 54min
The months with the most sunshine are June and July (Average sunshine: 9h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in September
Dover, IL
- Average sunshine days in September: 17.6 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is June (11.8 days).
Average UV index in September
Dover, IL
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Dover, IL
- Average cloud cover in September: 32
The month with the most cloud cover is January (Cloud cover 60).
The month with the least cloud cover is September (Cloud cover 32).
Average visibility in September
Dover, 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).
