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
The move into September indicates a slight reduction in the average high-temperature, down from August's warm 77°F (25°C) to an agreeable 70°F (21.1°C). During the nights in September, Charleston observes an average low-temperature of 49.8°F (9.9°C).Humidity
In September, the average relative humidity is 81%.Rainfall
In September, in Charleston, the rain falls for 13.5 days. Throughout September, 2.17" (55mm) of precipitation is accumulated. Throughout the year, in Charleston, there are 175.2 rainfall days, and 30.39" (772mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall in Charleston.Daylight
In Charleston, the average length of the day in September is 12h and 28min.On the first day of September, sunrise is at 6:35 am and sunset at 7:41 pm. On the last day of the month, sunrise is at 7:05 am and sunset at 6:51 pm EDT.
Sunshine
The average sunshine in September is 8.4h.UV index
In Charleston, the average daily maximum UV index in September is 3. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for the average person.Note: An average UV index of 3 in September transforms into this advice:
Exercise prudence. Persons with fair skin could be burned in under 30 minutes. Protect yourself from the midday Sun's peak UV radiation by minimizing exposure. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit.
Frequently asked questions
What is the average September temperature in Charleston?
What is the average humidity in September in Charleston?
How much does it rain in Charleston in September?
When it does not snow in Charleston?
Does it snow in Charleston in September?
How many hours of daylight does Charleston have in September?
When is the sunrise / sunset in September in Charleston?
How many hours of sunshine does Charleston have in September?
What is the UV index reading in September in Charleston?
Average temperature in September
Charleston, PA
- Average high temperature in September: 70°F
The warmest month (with the highest average high temperature) is July (79.3°F).
The month with the lowest average high temperature is January (28.6°F).
- Average low temperature in September: 49.8°F
The month with the highest average low temperature is July (57.2°F).
The coldest month (with the lowest average low temperature) is January (17.1°F).
Average pressure in September
Charleston, PA
- Average pressure in September: 30.07"Hg
The month with the highest atmospheric pressure is November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Charleston, PA
- Average wind speed in September: 6mph
The windiest month (with the highest average wind speed) is January (8.8mph).
The calmest month (with the lowest average wind speed) is August (5.5mph).
Average humidity in September
Charleston, PA
- Average humidity in September: 81%
The month with the highest relative humidity is February (86%).
The month with the lowest relative humidity is June (78%).
Average rainfall in September
Charleston, PA
- Average rainfall in September: 2.17"
The wettest month (with the highest rainfall) is April (3.35").
The driest month (with the least rainfall) is November (1.97").
Average rainfall days in September
Charleston, PA
- Average rainfall days in September: 13.5 days
The month with the highest number of rainy days is July (19.4 days).
The month with the least rainy days is February (8.5 days).
Average snowfall in September
Charleston, PA
- Average snowfall in September: 0"
The month with the highest snowfall is February (9.06").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Charleston, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (18.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Charleston, PA
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in September: 8h and 2min
The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is December (Average sunshine: 3h and 6min).
Average sunshine days in September
Charleston, PA
- Average sunshine days in September: 14 days
The month with the most sunshine days is September (14 days).
The month with the least sunshine days is February (7.4 days).
Average UV index in September
Charleston, PA
- Average UV index in September: 3
The months with the highest UV index are May, June, July and August (UV index 5).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Charleston, PA
- Average cloud cover in September: 43
The month with the most cloud cover is December (Cloud cover 69).
The months with the least cloud cover are July and August (Cloud cover 39).
Average visibility in September
Charleston, PA
- Average visibility in September: 5mi
The months with the highest visibility are January, March, April, May, June, July, August, September, October, November and December (5mi).
The month with the lowest visibility is February (4mi).
Charleston, Pennsylvania, USA
Weather forecast for your location
2. Allow the app to use your location
