Charleston in September
In September, Charleston averages 28°C (82°F) during the day and 22°C (72°F) at night, with frequent rain — about 21 days of the month see precipitation (157 mm total).
Off-peakConditions are warm and beach-friendly. Expect daily rain or showers, often in heavy bursts.
It's peak hurricane season in Charleston during September. Travel is possible but expect storm risk, possible flight disruption, and generally lower travel insurance coverage.
How September compares to the rest of the year in Charleston
September is in the middle of the year for warmth in Charleston (4th of 12) and moderately rainy compared to the rest of the year (4th of 12). Daytime temperature runs 5°C above the annual average (23°C). September runs 2°C cooler than August (30°C) and cools 4°C in October (24°C).
September sunrise & sunset in Charleston
Times shown for Charleston local time (America/New_York), calculated for the 15th of September. They shift by a few minutes day to day across the month.
Photography light in Charleston — September
Golden-hour and blue-hour windows for the 15th of September, in Charleston's local time. Use these for soft warm light (golden) or cool architectural twilight (blue).
📅 When to book — Charleston in September
Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on September's tier (Off-peak) and Charleston's popularity.
Crowds & pricing — September in Charleston
This is off-peak for Charleston — the lowest prices of the year and the fewest crowds, but with real trade-offs: some restaurants, hotels, and beach businesses may close for the season; weather conditions can make outdoor activities unpredictable; and a handful of seasonal sights run reduced hours or close entirely. Great if you prefer a quiet local rhythm and don't mind the climate giving you reasons to choose indoor activities.
Why this tier: peak hazard season (1 active)
Sun & mosquito risk — September in Charleston
UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.
Charleston in other months
| Month | Avg high | Avg low | Rainfall | Rain days | Snow days |
|---|---|---|---|---|---|
| January | 14°C / 58°F | 6°C / 44°F | 78 mm | 12 | — |
| February | 17°C / 62°F | 9°C / 48°F | 77 mm | 13 | — |
| March | 19°C / 67°F | 11°C / 53°F | 78 mm | 14 | — |
| April | 23°C / 73°F | 15°C / 59°F | 116 mm | 13 | — |
| May | 27°C / 80°F | 20°C / 67°F | 84 mm | 16 | — |
| June | 29°C / 85°F | 23°C / 74°F | 129 mm | 22 | — |
| July | 31°C / 88°F | 25°C / 77°F | 118 mm | 25 | — |
| August | 30°C / 86°F | 25°C / 76°F | 170 mm | 26 | — |
| September | 28°C / 82°F | 22°C / 72°F | 157 mm | 21 | — |
| October | 24°C / 76°F | 17°C / 63°F | 94 mm | 13 | — |
| November | 19°C / 66°F | 11°C / 52°F | 85 mm | 12 | — |
| December | 17°C / 62°F | 9°C / 49°F | 122 mm | 12 | — |
Other cities with similar September weather
🌍 See the full ranked list of climate twins for Charleston in September →
Frequently asked questions
How hot is Charleston in September?
In September, Charleston averages a high of 28°C (82°F) and a low of 22°C (72°F) — generally warm.
Does it rain a lot in Charleston in September?
September is quite rainy in Charleston, with about 21 rainy days on average.
Is September a good time to visit Charleston?
September is warm but on the rainy side. It suits travelers who are comfortable with warm weather; check the month-by-month ranking to compare it against the rest of the year.
What should I pack for Charleston in September?
Pack lightweight, breathable clothing, sunglasses and sunscreen, plus a compact umbrella or rain jacket. See the full September packing list for Charleston for a complete, climate-based checklist.
Check the live 10-day forecast and sunrise/sunset.