Charleston, SC Climate & Monthly Averages

South Carolina, United States 🇺🇸 · humid subtropical climate
Annual avg
67°
Hottest month
July
Coldest month
January
Rainy days / yr
136
Sunshine
9.6 h/day
Right now: 84° and heavy rain at times - see live conditions

The climate of Charleston

Charleston averages 67°F (20°C) across the year, with 9.6 hours of sunshine a day and 51.6 inches (1310 mm) of precipitation. The spread runs from January, at 58°F (15°C), to July, at 88°F (31°C).

Climate quick facts

  • Hottest month: July - highs near 88°F (31°C)
  • Coldest month: January - highs near 58°F (15°C)
  • Decade extremes (2015-2024): 98°F (37°C) high · 11°F (-11°C) low
  • Wettest month: August (19 rainy days) · Sunniest: June (11.6 h sun/day)
  • Climate type: humid subtropical
  • Annual swing: 17°C between the average warmest and coolest month · day to night: 7°C
  • Months averaging 30°C or hotter: 1
  • Average humidity: 76%

Temperatures through the year

January bottoms out at 58°F (15°C) in daylight, 44°F (7°C) after dark. Warmth peaks in July: highs of 88°F (31°C), lows of 77°F (25°C). Sunshine averages 9.6 hours a day over the year, peaking in June at 11.6 hours.

Rain, sun and snow

Five of the twelve months pair mild highs with fewer than twelve wet days; the longest unbroken run is March through May. Days and nights are about 7°C apart on average - narrower than about 80% of the cities we track. Precipitation concentrates in August - 7.0 inches (177 mm) on 19 days - and thins out by March. Across the gridded 2015-2024 daily record, the highest daily maximum for this location was 98°F (37°C) and the lowest daily minimum 11°F (-11°C).

How Charleston compares

  • Charleston sits close to the middle of our dataset on most measures: 67°F (20°C) as an annual average, 51.6 inches (1310 mm) of precipitation and 9.6 hours of sun a day.

Ranked against every city in our dataset, each measured on the same ten-year window.

Monthly climate table

Monthly averages for Charleston based on 2015–2024 weather data.
MonthHighLow Rain daysPrecipitation SunshineHumidity
January 58° 44° 10 3.2 in 7.6 h/day 73%
February 62° 48° 9 3.3 in 8.0 h/day 76%
March 67° 53° 9 3.0 in 8.9 h/day 72%
April 73° 59° 8 4.3 in 10.8 h/day 70%
May 80° 67° 11 3.5 in 11.5 h/day 73%
June 85° 74° 16 4.8 in 11.6 h/day 77%
July 88° 77° 17 4.9 in 11.5 h/day 78%
August 86° 76° 19 7.0 in 10.7 h/day 81%
September 83° 72° 14 5.9 in 9.9 h/day 79%
October 76° 63° 7 3.7 in 9.3 h/day 75%
November 67° 53° 8 3.2 in 8.2 h/day 75%
December 62° 49° 9 4.8 in 7.0 h/day 77%

Charleston month by month

Charleston weather in January

January brings highs around 58°F (15°C), lows near 44°F (7°C), about 10 wet days - typically the coldest month of the year in Charleston.

Charleston weather in February

February brings highs around 62°F (17°C), lows near 48°F (9°C), about 9 wet days.

Charleston weather in March

March brings highs around 67°F (20°C), lows near 53°F (12°C), about 9 wet days - typically the driest month of the year in Charleston.

Charleston weather in April

April brings highs around 73°F (23°C), lows near 59°F (15°C), about 8 wet days.

Charleston weather in May

May brings highs around 80°F (27°C), lows near 67°F (20°C), about 11 wet days.

Charleston weather in June

June brings highs around 85°F (29°C), lows near 74°F (23°C), about 16 wet days - typically the sunniest month of the year in Charleston.

Charleston weather in July

July brings highs around 88°F (31°C), lows near 77°F (25°C), about 17 wet days - typically the hottest month of the year in Charleston.

Charleston weather in August

August brings highs around 86°F (30°C), lows near 76°F (24°C), about 19 wet days - typically the wettest month of the year in Charleston.

Charleston weather in September

September brings highs around 83°F (28°C), lows near 72°F (22°C), about 14 wet days.

Charleston weather in October

October brings highs around 76°F (25°C), lows near 63°F (17°C), about 7 wet days.

Charleston weather in November

November brings highs around 67°F (20°C), lows near 53°F (12°C), about 8 wet days.

Charleston weather in December

December brings highs around 62°F (16°C), lows near 49°F (9°C), about 9 wet days.

Seasons in Charleston

Spring (March through May)

Through spring, Charleston is mild and warm: 73°F (23°C) by day, 60°F (15°C) after dark, and expect showers on roughly 28 days across the season. Daylight is generous - around 10.4 hours of sun a day.

Summer (June through August)

Summer runs hot here - highs near 86°F (30°C), nights near 76°F (24°C), and rain falls on around 52 of the 90 days. Daylight is generous - around 11.3 hours of sun a day. With the moisture factored in, afternoons feel hotter than the reading suggests - the humidity and dew point converter shows why.

Fall (September through November)

Through fall, Charleston is mild and warm: 76°F (24°C) by day, 63°F (17°C) after dark, and expect showers on roughly 29 days across the season.

Winter (December through February)

Through winter, Charleston is mild: 61°F (16°C) by day, 47°F (8°C) after dark, and expect showers on roughly 27 days across the season.

Climate questions, answered

How much do temperatures drop at night in Charleston?
By about 7°C on an average day - a narrower day-to-night gap than most of the 3496 cities we track. In July that means 88°F (31°C) down to 77°F (25°C).
Is Charleston humid?
Relative humidity averages 76% across the year, which reads as fairly humid. Paired with July heat, muggy afternoons are routine.
Is Charleston cold in winter?
January nights average 44°F (7°C). Chilly rather than harsh - hard freezes are uncommon.
Is Charleston hot in summer?
July averages 88°F (31°C). Hot afternoons happen but extremes are not the norm.
What is the average temperature in Charleston?
67°F (20°C) across all twelve months - about 74°F (23°C) by day and 61°F (16°C) after dark.
What should I pack for Charleston?
It depends on the month: July runs to 88°F (31°C) while January holds at 58°F (15°C). The full month-by-month breakdown is in the packing notes above.

Best time to visit Charleston

The best time to visit Charleston is generally February to May and October to November, when warm days, manageable rainfall and plenty of daylight line up. Daytime temperatures in that window sit near 71°F (22°C), with rain on about 9 days a month. For the same question asked the other way round, see where else is warm in February.

Pack for Charleston with light clothing for the warm months, a compact umbrella or rain shell and moisture-wicking fabrics for the humidity. Even in July, lows of 77°F (25°C) make an extra layer worth the space.

Charleston temperature records (2015-2024)

Highest recorded
98°
in July
Lowest recorded
11°
in January
Annual precipitation
51.6"
Snowy days / yr
0

Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.