September weather forecastColchester, IL
September
Weather in September
September, the first month of the autumn in Colchester, is still a warm month, with an average temperature fluctuating between 76.8°F (24.9°C) and 57.6°F (14.2°C).Temperature
September reports an average high-temperature of a still warm 76.8°F (24.9°C), slightly varied from August's 82°F (27.8°C). Throughout September, the average low-temperature in Colchester dips to a moderate 57.6°F (14.2°C).Humidity
In Colchester, the average relative humidity in September is 75%.Rainfall
In Colchester, in September, it is raining for 7.7 days, with typically 0.87" (22mm) of accumulated precipitation. Throughout the year, there are 94.4 rainfall days, and 7.76" (197mm) of precipitation is accumulated.Snowfall
In Colchester, snow does not fall in May through September.Daylight
In Colchester, the average length of the day in September is 12h and 27min.On the first day of the month, sunrise is at 6:31 am and sunset at 7:34 pm. On the last day of September, sunrise is at 6:59 am and sunset at 6:46 pm CDT.
Sunshine
In September, the average sunshine is 9.4h.UV index
The average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV radiation for ordinary individuals.Note: In September, a daily UV index of 4 turns into the following recommendations:
Exercise prevention - Precautions against solar damage are endorsed. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. During bright days, sunglasses that offer UVA and UVB defense are recommended.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Colchester, 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 (31.1°F).
- Average low temperature in September: 57.6°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 (19°F).
Average pressure in September
Colchester, 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
Colchester, IL
- Average wind speed in September: 7.5mph
The windiest month (with the highest average wind speed) is January (10.5mph).
The calmest months (with the lowest average wind speed) are July and August (6.6mph).
Average humidity in September
Colchester, 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
Colchester, IL
- Average rainfall in September: 0.87"
The wettest month (with the highest rainfall) is May (1.1").
The driest month (with the least rainfall) is December (0.35").
Average rainfall days in September
Colchester, IL
- Average rainfall days in September: 7.7 days
The month with the highest number of rainy days is May (12.3 days).
The month with the least rainy days is January (3.3 days).
Average snowfall in September
Colchester, IL
- Average snowfall in September: 0"
The month with the highest snowfall is January (0.67").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Colchester, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (6.3 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
Colchester, 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 24min
The months with the most sunshine are June and July (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in September
Colchester, IL
- Average sunshine days in September: 20.4 days
The month with the most sunshine days is December (23.5 days).
The month with the least sunshine days is June (13.9 days).
Average UV index in September
Colchester, IL
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in September
Colchester, IL
- Average cloud cover in September: 30
The month with the most cloud cover is January (Cloud cover 55).
The month with the least cloud cover is August (Cloud cover 29).
Average visibility in September
Colchester, 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).
