Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
Charleston records an average high-temperature of a still warm 77.2°F (25.1°C) as September arrives, nearly mirroring the previous month's climate. In the month of September, Charleston witnesses a consistent average low-temperature of 58.5°F (14.7°C).Humidity
The average relative humidity in September in Charleston is 76%.Rainfall
In Charleston, in September, it is raining for 12.1 days, with typically 1.38" (35mm) of accumulated precipitation. Throughout the year, there are 148 rainfall days, and 25.63" (651mm) of precipitation is accumulated.Snowfall
In Charleston, snow does not fall in May through September.Daylight
In September, the average length of the day in Charleston is 12h and 26min.On the first day of the month, sunrise is at 6:21 am and sunset at 7:23 pm. On the last day of September, in Charleston, sunrise is at 6:48 am and sunset at 6:36 pm CDT.
Sunshine
The average sunshine in September in Charleston is 8.9h.UV index
The average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a medium vulnerability from unsafe exposure to UV radiation for the average person.Note: The UV index of 5 during September leads to these advisories:
Take heed. Individuals of lighter complexion can be burned in less than half an hour. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades.
Frequently asked questions
What is the temperature in September in Charleston?
What is the average humidity in September in Charleston?
How many days does it rain in September in Charleston?
When it does not snow in Charleston?
Does it snow in Charleston in September?
How many hours of daylight does Charleston have in September?
What time are sunrise and sunset in September in Charleston?
How long on average sun shines in September in Charleston?
How high is the UV index in September in Charleston?
Average temperature in September
Charleston, IL
- Average high temperature in September: 77.2°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (34°F).
- Average low temperature in September: 58.5°F
The month with the highest average low temperature is July (65.8°F).
The coldest month (with the lowest average low temperature) is January (21.9°F).
Average pressure in September
Charleston, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Charleston, IL
- Average wind speed in September: 7.1mph
The windiest month (with the highest average wind speed) is January (10.7mph).
The calmest month (with the lowest average wind speed) is July (6.2mph).
Average humidity in September
Charleston, IL
- Average humidity in September: 76%
The month with the highest relative humidity is July (83%).
The month with the lowest relative humidity is October (70%).
Average rainfall in September
Charleston, IL
- Average rainfall in September: 1.38"
The wettest month (with the highest rainfall) is April (3.31").
The driest month (with the least rainfall) is February (1.3").
Average rainfall days in September
Charleston, IL
- Average rainfall days in September: 12.1 days
The month with the highest number of rainy days is May (16.8 days).
The month with the least rainy days is February (7.8 days).
Average snowfall in September
Charleston, IL
- Average snowfall in September: 0"
The month with the highest snowfall is December (2.13").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Charleston, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (8.1 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
Charleston, IL
- Average daylight in September: 12h and 2min
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 24min).
- Average sunshine in September: 8h and 5min
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 0min).
Average sunshine days in September
Charleston, IL
- Average sunshine days in September: 15.7 days
The month with the most sunshine days is October (18.3 days).
The month with the least sunshine days is July (10.6 days).
Average UV index in September
Charleston, IL
- Average UV index in September: 5
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Charleston, IL
- Average cloud cover in September: 32
The month with the most cloud cover is January (Cloud cover 56).
The month with the least cloud cover is June (Cloud cover 31).
Average visibility in September
Charleston, 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).
Charleston, Illinois, USA
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