Climate averages 1991–2020
Charleston weather
in December.
A mild, moderately wet month: the joint 10th warmest and the 7th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a mild month in Charleston: daytime highs average 15.9°C and nights cool to about 8.9°C. By daytime temperature it is the joint 10th warmest of the 12 months.
Expect about 86 mm of rain on roughly 8 days, which makes December a moderately wet month (the 7th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 10 h 02 min on an average December day.
The nearest other city in this atlas is North Charleston (10 km away). In December its highs average 15.8°C, about as warm as Charleston, with 86 mm of rain.
Among the 498 cities listed in the United States, Charleston ranks 135th of 498 for the warmest December highs and joint 304th of 498 for the driest December (rainfall, lowest first). The mean December high of those 498 cities is 10.5°C; Charleston is 5.4°C warmer than that mean.
From December to January, average highs fall by 1.5°C to 14.4°C, and monthly rainfall falls from 86 mm to 81 mm.
The annual picture
December in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Charleston climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 14.4°C7.1°C | 7.1°C | 81 | 8.4 | 10.310 h |
| February | 15.9°C8.4°C | 8.4°C | 84 | 7.8 | 11.011 h |
| March | 18.6°C11.2°C | 11.2°C | 81 | 8.2 | 12.012 h |
| April | 22.3°C15.0°C | 15.0°C | 74 | 7.5 | 13.013 h |
| May | 26.2°C19.5°C | 19.5°C | 68 | 9.0 | 13.814 h |
| June | 29.0°C23.2°C | 23.2°C | 130 | 16.3 | 14.314 h |
| July | 30.4°C24.9°C | 24.9°C | 138 | 17.7 | 14.114 h |
| August | 29.6°C24.5°C | 24.5°C | 160 | 18.9 | 13.413 h |
| September | 27.6°C22.2°C | 22.2°C | 128 | 13.2 | 12.412 h |
| October | 23.8°C17.3°C | 17.3°C | 101 | 7.8 | 11.411 h |
| November | 19.1°C12.1°C | 12.1°C | 65 | 6.7 | 10.511 h |
| December, selected | 15.9°C8.9°C | 8.9°C | 86 | 7.6 | 10.010 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
December in nearby cities
- North Charleston in DecemberUnited States · 10 kmHigh 15.8°C · Low 7.5°C · 86 mm rain
- Savannah in DecemberUnited States · 134 kmHigh 16.4°C · Low 8.1°C · 86 mm rain
- Columbia (South Carolina), United States in DecemberUnited States · 170 kmHigh 13.6°C · Low 4.2°C · 93 mm rain
- Wilmington (North Carolina), United States in DecemberUnited States · 245 kmHigh 14.5°C · Low 7.1°C · 97 mm rain
- Rock Hill in DecemberUnited States · 259 kmHigh 11.9°C · Low 3.1°C · 96 mm rain
- Fayetteville in DecemberUnited States · 271 kmHigh 12.8°C · Low 3.7°C · 93 mm rain
- Charlotte in DecemberUnited States · 285 kmHigh 11.2°C · Low 2.1°C · 93 mm rain
- Concord (North Carolina), United States in DecemberUnited States · 299 kmHigh 11.2°C · Low 2.5°C · 94 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Charleston) is explained once on the Charleston year overview and on the Sources, method and limits page.
North Charleston lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.