Charleston City, South Carolina climate: Climate normals at a NOAA weather station
Charleston City's normal year runs from 44°F January nights to 88°F July afternoons, with 44.3 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 19.6°C, January lows of 6°C, July highs of 31°C, 1,124 mm of precipitation a year.
- NOAA stationCharleston City
- Station IDUSW00013782
- Location32.78°N 79.93°W
- Elevation10 ft (3 m)
On October 23, the normal high in Charleston City is 74°F and the normal low 61°F, and the chance of measurable rain or snow is 21%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Charleston City.
- Jan 58° 44°
- Feb 60° 46°
- Mar 66° 52°
- Apr 72° 60°
- May 79° 68°
- Jun 84° 74°
- Jul 88° 77°
- Aug 86° 77°
- Sep 83° 73°
- Oct 76° 63°
- Nov 67° 53°
- Dec 61° 47°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like at Charleston City each month?
July is the warmest month, with normal highs of 88°F; January the coldest, with normal lows of 44°F. The most precipitation falls in August (6.11 in), the least in November (2.30 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 58°F | 44°F | 50.8°F | 2.56 | 8 | <1 | 4 | 10 h 10 min |
| February | 60°F | 46°F | 53.2°F | 2.56 | 8 | <1 | 1 | 11 h |
| March | 66°F | 52°F | 58.8°F | 3.03 | 8 | <1 | <1 | 12 h |
| April | 72°F | 60°F | 66.0°F | 2.96 | 7 | <1 | <1 | 13 h |
| May | 79°F | 68°F | 73.5°F | 2.58 | 7 | 2 | <1 | 13 h 50 min |
| June | 84°F | 74°F | 79.2°F | 4.85 | 11 | 5 | <1 | 14 h 20 min |
| July | 88°F | 77°F | 82.3°F | 5.08 | 12 | 9 | <1 | 14 h 10 min |
| August | 86°F | 77°F | 81.4°F | 6.11 | 12 | 7 | <1 | 13 h 20 min |
| September | 83°F | 73°F | 77.6°F | 5.25 | 9 | 2 | <1 | 12 h 30 min |
| October | 76°F | 63°F | 69.4°F | 4.07 | 7 | <1 | <1 | 11 h 30 min |
| November | 67°F | 53°F | 60.1°F | 2.30 | 6 | <1 | <1 | 10 h 30 min |
| December | 61°F | 47°F | 53.8°F | 2.91 | 9 | <1 | 1 | 10 h |
| Year (annual) | 73°F | 61°F | 67.2°F | 44.26 | 102 | 25 | 6 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 14°C | 6°C | 10.4°C | 65 mm |
| February | 16°C | 8°C | 11.8°C | 65 mm |
| March | 19°C | 11°C | 14.9°C | 77 mm |
| April | 22°C | 15°C | 18.9°C | 75 mm |
| May | 26°C | 20°C | 23.1°C | 66 mm |
| June | 29°C | 23°C | 26.2°C | 123 mm |
| July | 31°C | 25°C | 27.9°C | 129 mm |
| August | 30°C | 25°C | 27.4°C | 155 mm |
| September | 28°C | 23°C | 25.3°C | 133 mm |
| October | 24°C | 17°C | 20.8°C | 103 mm |
| November | 19°C | 12°C | 15.6°C | 58 mm |
| December | 16°C | 8°C | 12.1°C | 74 mm |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00013782; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
Which months are mildest at Charleston City?
Normal highs sit between 65°F and 85°F in March, April, May, June, September, October and November. Of those, November has the fewest days with rain (6).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00013782.
When is the last frost at Charleston City?
In Charleston City, the last spring frost (32°F) comes after February 4 in half of years and after March 4 in one year in ten; the first autumn frost comes before December 30 in half of years and before December 2 in one year in ten. A night at 32°F or colder comes at all in 92% of years here (NOAA).
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- February 41 year in 10 after March 4; 9 in 10 after January 5
- First autumn frost, half of years before
- December 301 year in 10 before December 2; 9 in 10 before January 25
NOAA puts the median frost-free season at 321 days, and the season without a hard freeze (28°F) at 352 days.
A hard freeze (28°F) comes after January 24 in half of springs and before January 8 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Charleston City in zone 9a in ZIP code 29401, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, the station is in zone 9b: the coldest night of a typical year reaches 27°F (30 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in South Carolina · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00013782; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get at Charleston City?
In a normal year in Charleston City, 25 days a year reach 90°F, 6 nights fall to 32°F or colder and 102 days bring measurable precipitation.
- Days at 90°F or more
- 25a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 6a normal year
- Days that stay below freezing
- fewer than 1high of 32°F or less
- Days with 0.01 inch of precipitation
- 102a normal year
The highest temperature in this station's record (since 1893) is 104°F, on June 24, 1944; the lowest is 7°F, on February 14, 1899.
The wettest calendar year on that record is 1945, with 74.87 in; the snowiest season is 1898–99, with 3.9 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00013782; records: ACIS (NOAA Regional Climate Centers), station USW00013782. Records use complete months only; a month missing more than three days is left out.
How sunny is it at Charleston City?
Over a year 80% of the sunlight that would reach the ground under clear skies gets through the clouds at Charleston City, 4.7 kWh per square metre a day. May is the sunniest month (85%) and February the cloudiest (73%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 74% | 2.8 |
| February | 73% | 3.5 |
| March | 76% | 4.6 |
| April | 84% | 6.0 |
| May | 85% | 6.5 |
| June | 84% | 6.5 |
| July | 84% | 6.3 |
| August | 82% | 5.7 |
| September | 79% | 4.8 |
| October | 81% | 4.1 |
| November | 78% | 3.1 |
| December | 73% | 2.5 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How many heating and cooling degree days does Charleston City record?
A normal year at Charleston City brings 1,623 heating degree days, 70% fewer than the median U.S. place (5,373), and 2,448 cooling degree days, 2.7 times the median (908). Three months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 6,519 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 442 | 2 |
| February | 334 | 3 |
| March | 213 | 21 |
| April | 62 | 92 |
| May | 6 | 269 |
| June | 0 | 428 |
| July | 0 | 536 |
| August | 0 | 510 |
| September | 1 | 377 |
| October | 33 | 169 |
| November | 181 | 34 |
| December | 353 | 7 |
| Year (annual) | 1,623 | 2,448 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00013782. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Have recent years at Charleston City been warmer than normal?
2025 averaged 67.5°F, 0.3°F above the 1991-2020 normal of 67.2°F. 5 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 69.0°F | +1.8°F | 45.53 |
| 2022 | 68.0°F | +0.8°F | 39.20 |
| 2023 | 68.6°F | +1.4°F | 49.32 |
| 2024 | 68.6°F | +1.4°F | 49.12 |
| 2025 | 67.5°F | +0.3°F | 41.95 |
Over 146 complete years from 1871 to 2025, the station's annual mean temperature rose at a fitted 0.4°F per century (+0.02°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USW00013782; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Charleston City's climate compare?
Charleston City is warmer than 72 of the 73 places with their own NOAA record in South Carolina, and wetter than 5. Across the 7,247 U.S. stations with normals, its annual mean of 67.2°F is warmer than 92%.
In the Köppen classification computed from these normals, Charleston City is Cfa: temperate, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Charleston City share this climate record?
3 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- James Island, SC12,451 people · 3 mi S
- Folly Beach, SC2,084 people · 8 mi S
- Kiawah Island, SC2,003 people · 14 mi SW
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Charleston City's climate
What is the coldest month at Charleston City?
January, with a normal high of 58°F and a normal low of 44°F. The warmest is July (88°F by day, 77°F at night).
What is the rainiest month at Charleston City?
August, with 6.11 in of precipitation in a normal year; the driest is November with 2.30 in.
What plant hardiness zone is Charleston City in?
The USDA's 2023 map puts Charleston City in zone 9a in ZIP code 29401, the nearest ZIP area. By the same method at the station, the coldest night of a typical year reaches 27°F (30 years, 1991-2020): zone 9b.
How late can frost come at Charleston City?
In half of years the last 32°F night comes after February 4; in one year in ten it comes after March 4. Waiting until March 4 leaves about a one-in-ten chance of a later frost.
Nearby and next
- South Carolina climateThe statewide normals and every place in the state
- Sullivan's Island, SC4 miles from this station, 65.5°F a year
- Charleston, SC11 miles from this station, 66.5°F a year
- Summerville, SC25 miles from this station, 63.8°F a year
- Edisto Island Middleton Plantation, SC26 miles from this station, 66.7°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made