US · Charleston
Charleston International Airport
KCHS · Climate normals 1991-2020
Twelve monthly averages for KCHS, computed from NOAA GSOD observations over 1991-2020. These are typical values for each month — averages, not a forecast and not a substitute for the current METAR/TAF. A single month can differ from its normal by several degrees and still be normal.
Source: NOAA GSOD · Period 1991-2020 · imported 2026-11-02 · Download these values (JSON)
Annual cycle
Monthly means · °C and mm · 1991-2020- Daily range (mean max – mean min)†
- Mean temperature
- Precipitation total
Month by month
NOAA GSOD · 1991-2020| Month | Mean | Mean max† | Mean min† | Precipitation | Wet days |
|---|---|---|---|---|---|
| January | 9.7 °C | 17.1 °C | 3.3 °C | 89.5 mm | 10.2 d |
| February | 11.3 °C | 19.0 °C | 4.5 °C | 84.6 mm | 9.8 d |
| March | 14.7 °C | 22.4 °C | 7.8 °C | 91.1 mm | 9.2 d |
| April | 18.6 °C | 26.0 °C | 11.7 °C | 87.7 mm | 9.4 d |
| May | 22.7 °C | 29.5 °C | 16.6 °C | 86.5 mm | 8.8 d |
| June | 25.9 °C | 32.0 °C | 20.9 °C | 159.7 mm | 12.7 d |
| July | 27.5 °C | 33.3 °C | 22.9 °C | 167.9 mm | 13.9 d |
| August | 26.9 °C | 32.5 °C | 22.6 °C | 180.2 mm | 14.0 d |
| September | 24.5 °C | 30.3 °C | 19.9 °C | 163.8 mm | 11.7 d |
| October | 19.6 °C | 26.3 °C | 13.7 °C | 121.2 mm | 8.7 d |
| November | 14.4 °C | 21.9 °C | 7.9 °C | 72.9 mm | 8.6 d |
| December | 11.1 °C | 18.3 °C | 4.8 °C | 91.2 mm | 10.7 d |
| Year | 18.9 °C | 25.7 °C | 13.0 °C | 1396.3 mm | 128 d |
Wet day = day with at least 0.25 mm of precipitation. The annual row is the mean of the twelve monthly means and the sum of the twelve monthly totals, so it can be reproduced from the table. † Mean max and mean min come from GSOD's daily extremes over the synoptic observations of each day, not from a calendar-day extreme: they read roughly 0.5–1.5 °C wider than the official normals of the same station. The mean temperature and the precipitation are unaffected.
Annual summary
1991-2020- Mean temperature18.9 °C
- Total precipitation1396.3 mm
- Wettest monthAugust180.2 mm
- Driest monthNovember72.9 mm
- Warmest monthJuly27.5 °C
- Coldest monthJanuary9.7 °C
Compared with our own archive
station_month · METAR observationsThe observed archive is too young to compare. We have 0 complete months of our own observations for KCHS (from 2026-10-29); 3 are needed before a monthly comparison means anything.
No comparison is shown rather than one drawn from a handful of days. The normals above come from NOAA GSOD and do not depend on our archive.