Charleston weather in May
Temperature, sea and sunshine in May: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in May
Excellent
Best time to visit: May – October
What is the weather like in Charleston in May?
In May, Charleston is warm: daytime highs average 26 °C, and nights cool down to about 20 °C. The sea averages 22.9 °C – refreshing for a swim. The sun shines for around 8 hours a day. Rain is frequent, with about 9 rainy days and 69 mm in total. The air is often humid and muggy. All in all, May is an excellent month for a holiday in Charleston.
May compared
How the weather changes from April to June. Tap a month to open it.
More details for May
- Daylight
- 13 h 49 min06:21 – 20:10
- UV index
- 11 · extremeclear sky, noon (estimate)All months
- Muggy days
- 18 daysdew point 18 °C or moreAll months
- Wind
- 19 km/haverage daily peakAll months
- Cloud cover
- 50 %on averageAll months
- Hot days
- 2 days30 °C or moreAll months
- Time zone
- UTC−4America/New_York
How the score comes together
- Temperatureweight 35 %100 %
- Seaweight 25 %84 %
- Sunshineweight 20 %83 %
- Few rainy daysweight 20 %62 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Sun, sea & sand”.
What to pack in May
- Swimwear
- Sunscreen
- Sunglasses & sun hat
- Light, breathable clothes
- Insect repellent
- Rain jacket or umbrella
Charleston in May: quick answers
Is Charleston hot in May?
Warm rather than hot: in May, daytime highs in Charleston average 26 °C and nights cool to about 20 °C. On about 2 days the thermometer climbs to 30 °C or more.
Can you swim in Charleston in May?
Yes. In May the sea averages 22.9 °C – refreshing for a swim.
Does it rain much in Charleston in May?
Rain is frequent, with about 9 rainy days and 69 mm in total.
Charleston month by month
The whole year in CharlestonAll destinations: USAWhere to go in MaySea temperature in May
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences