The month in detail
What to expect in September
Autumn in Charleston is often underrated: 28°C, golden light and declining crowds. An interesting window. Expect rain on 30% of days — a light raincoat in the bag is recommended. A good balance between weather and crowds, even if May (8.6/10) remains theoretically better.
September ranks 3 out of 12 months in Charleston. Compared to August: −2°C daytime, 11 pts fewer rainy days, +0.5h of sun per day.
This month's conditions
What it's like in September
UV index
6 · high
sunscreen and hat advised
Feels like
muggy at times
21°
Sea
27°C
warm, ideal
Daylight
12.2h of daylight
Air quality
good
AQI 31
Compare
Is September the right month?
The best month in Charleston is May (8.6/10), 0.3 pt higher than September.
Book
Plan your trip
Hotels at their lowest outside peak season, highest on comfortable months. Shoulder seasons offer a good price/climate compromise.
Stay
Hotels & rentals · Charleston
Expedia →
Activities
Tours, tickets, experiences
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Flights
Multi-airline comparator
Kiwi →
🎟️ Activities & tours · Charleston
GetYourGuide selection · free cancellation
Practical info
What you need to know before you go
Three angles: the country (language, currency, safety, budget), the year-round climate, and the specifics of a beach holiday.
Country · United States
🗣️LanguageEnglish
💶CurrencyUS Dollar ($)
🚗DrivingRight-hand
🛡️Safety ⓘVery safe · 1/5
💰Cost of living ⓘExpensive · 4/5
🌡️ Climate
🌍Climate typeTemperate oceanic
📈Climate trend ⓘStable
🔥Hottest monthJuly · 31°C
❄️Coolest monthJanuary · 14°C
🌧️Rainiest month ⓘAugust · 41%
🏖️ Beach holiday
📅Peak seasonJuin → Sept
🏖️Swell (Sept–Mar) ⓘModérée
Explore
Other destinations in September
If September doesn't convince you for this destination, compare with others.
Similar climate
SavannahUnited States
New OrleansUSA
Saint AugustineUnited States
Outer BanksUnited States
SuzhouChinaLocation
Where is Charleston ?
Global position + regional geographic context.
🌍 World
🔍 Geographic context
Temperate oceanic climate with a 8.6 → 4.4 gap between best and worst month. 10 years of ERA5 data to choose by project.
32.78°N · 79.93°W
Questions
Frequently asked questions
What is the best time to visit Charleston?
May is the best month with 27.0°C highs, 20.0°C lows, 8.0h of sunshine and 25.0% rainy days. The months of May & April offer comparable conditions.
How many hours of sunshine does Charleston get in May?
Charleston averages 8.0 sunshine hours per day in May. It is the sunniest month with a climate score of 8.0/10.
What is the rainiest month in Charleston?
January is the most unfavourable month with January has the lowest climate score of the year and the lowest climate score of the year.
What are the temperatures at night in Charleston in May?
In May, overnight lows reach 20.0°C, while afternoon highs average 27.0°C.
Is Charleston good in winter?
In winter (December-February), Charleston scores 6.1/10 on average — Decent period conditions for cultural visits.. The best month overall remains May with a score of 8.0/10.
When should you avoid Charleston?
January is the most difficult month to visit Charleston, with January has the lowest climate score of the year. Climate conditions are at their lowest of the year during this period.
Can you swim in Charleston in September?
In September, the sea averages 27°C in Charleston: warm, ideal. Ideal conditions for swimming and snorkeling.
Do you need sun protection in Charleston in September?
The average UV index reaches 6 in September in Charleston (high), with about 12.2h of daylight. Sunscreen and hat advised.




