Avg High
Charleston in September
Verdict
In Charleston, September has a distinct autumn feel. As the season moves along, the air is cooling down. You can usually expect a warm month that feels variable day to day. Breezes can be part of the character, especially in exposed spots.
It suits travellers who want straightforward weather for sightseeing and day trips. Lookouts and coastal walks can feel sharper when the wind is up.
Avg Low
Rain
Daylight
12h
What to expect
- Daytime feel - Summer-like warmth that stay fairly consistent through the day. It can feel warmer than expected in the sun.
- Rain pattern - Very wet. Waterproof footwear becomes genuinely useful. Outdoor plans benefit from flexibility.
- Sun exposure - Sun protection matters. Cloud cover doesn't always mean low UV, so still protect your skin. Even short walks can add up.
- Breezes - A steady breeze, and expect sharp gusts that can change plans in exposed areas. Sheltered streets can feel fine, but open areas feel very different.
September in context
How it compares to the rest of the year in Charleston.
Hottest (avg)
#4 / 12
Wettest (avg)
#3 / 12
Daylight Hours
#6 / 12
Windiest (avg)
#8 / 12
Highest UV
#6 / 12
Most Humid
#3 / 12
Temperature
- Daytime high
-
- Nighttime low
-
- Feels like (avg)
-
Sunshine
- Daylight
- 12.4 hours
- UV index (max)
- 8
- Typical sun hours
- 06:03 – 18:24
Rain & Snow
- Total
-
- Rainy days
- 17
- Cloud cover
- 55%
- Snowfall
-
Humidity & Wind
- Humidity (avg)
- 79%
- Wind (avg)
-
- Wind (max gusts)
-
Frequently asked questions
Is September a good time to visit Charleston?
Typical September days in Charleston reach highs of 28°C (82°F) with nights around 22°C (72°F). It usually feels hot by day and mild after dark. It is among the wetter months, so it is wise to have some indoor backup plans or flexible activities.
What are temperatures like in September?
In September, you can usually expect highs of 28°C (82°F) and lows near 22°C (72°F). That means hot days and mild nights, so pack layers you can add or remove.
How much does it rain in September?
Rainfall in September averages 131 mm (5.2 in) across roughly 17 days. Overall it is a very wet time of year, so a light rain jacket and waterproof shoes are very handy.
How many hours of daylight are there in September?
You can expect about 12 hours of daylight in September. Sunrise is typically around 06:03 and sunset near 18:24. Daylight is fairly typical, with enough time for sightseeing.
How strong is the sun in September?
UV levels are often high (around 8). Regular sunscreen and a hat are recommended.
Is it windy in September?
In September, average wind speeds are around 13 km/h (8 mph), with gusts on the windiest days reaching about 50 km/h (31 mph). On the ground, it is it often feels breezy, especially in more exposed spots or along the coast.