Aiken climate — normals and trends
Aiken (United States) has a humid subtropical climate (Cfa) under the Köppen-Geiger classification. Its mean annual temperature is 17.7 °C and it receives 1,061 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is July (27.0 °C on average) and the coldest is January (7.7 °C). Rainfall peaks in July.
Aiken averages 30 frost days, 97 hot days (≥ 30 °C) and 122 rainy days per year.
Aiken has warmed by +1.2 °C between 1940 and 2025, or +0.14 °C per decade. This trend is statistically significant.
The hottest day of the period reached 43.0 °C (on 30 June 2012) and the coldest -19.2 °C (on 21 January 1985).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
AikenSouth Carolina
- coords
- 33.56°, -81.72°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
17.7°C
Average daily high
23.6°C
Average daily low
12.6°C
Annual rainfall
1,061mm
Sunshine / day
9.3h
Mean relative humidity
69%
Average peak wind
15.4km/h
Seasonal range
19.3°C
Frost days (< 0 °C)
30 d/yr
Hot days (≥ 30 °C)
97 d/yr
Rainy days (≥ 1 mm)
122 d/yr
Annual snowfall
2.8 cm
Average feels-like high
23.8 °C
Average feels-like low
11.8 °C
Average peak gust
34.5 km/h
Tropical nights (≥ 20 °C)
100 d/yr
Solar radiation
16.3 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.2 °C
since 1940
+0.1 °C per decade · r² = 0.29 · p = < 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
43.0 °C
30 June 2012
Coldest day
-19.2 °C
21 January 1985
Wettest day
208 mm
4 October 2015
Windiest day
60.1 km/h
27 September 2024
Strongest gust
140.0 km/h
27 September 2024
Hottest feels-like
45.7 °C
21 August 1983
Coldest feels-like
-25.4 °C
21 January 1985
Snowiest day
21.1 cm
10 February 1973
Sunniest day
13.9 h
19 June 2022
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 11.2 °C | -2.1 °C | 59 mm | -31 mm |
| Feb | 18.1 °C | +2.7 °C | 35 mm | -57 mm |
| Mar | 22.9 °C | +3.4 °C | 81 mm | -23 mm |
| Apr | 27.2 °C | +2.9 °C | 52 mm | -24 mm |
| May | 28.0 °C | -0.2 °C | 187 mm | +107 mm |
| Jun | 32.1 °C | +0.8 °C | 97 mm | +3 mm |
| Jul | 34.0 °C | +1.6 °C | 130 mm | +16 mm |
| Aug | 29.0 °C | -2.8 °C | 240 mm | +132 mm |
| Sep | 29.7 °C | +0.6 °C | 15 mm | -71 mm |
| Oct | 23.2 °C | -1.1 °C | 61 mm | -5 mm |
| Nov | 22.1 °C | +3.0 °C | 10 mm | -58 mm |
| Dec | 15.1 °C | +0.5 °C | 79 mm | -4 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Aiken?
Aiken has a humid subtropical climate (Köppen Cfa). Over 1940-2025, the average annual temperature is 17.7 °C and it receives 1,061 mm of precipitation per year.
What is the hottest day ever recorded in Aiken?
The hottest day measured in Aiken between 1940 and 2025 was 30 June 2012, reaching 43.0 °C.
What is the coldest day in Aiken?
The coldest day measured in Aiken between 1940 and 2025 was 21 January 1985, at -19.2 °C.
Does it snow in Aiken?
Yes. Aiken gets on average 2.8 cm of snow per year and has around 30 frost days.
Has the climate of Aiken warmed?
Yes: Aiken warmed by +1.2 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Aiken?
The wettest day measured in Aiken between 1940 and 2025 was 4 October 2015, with 208 mm of rain in 24 hours.
What was the windiest day in Aiken?
The windiest day measured in Aiken between 1940 and 2025 was 27 September 2024, with winds reaching 60.1 km/h.
What is the warmest month in Aiken?
The warmest month in Aiken is July (27.0 °C on average); the coldest is January (7.7 °C).
How much does it rain in Aiken?
Aiken receives on average 1,061 mm of precipitation per year, spread over about 122 rainy days.
Is it sunny in Aiken?
Aiken gets on average 9.3 hours of sunshine per day, roughly 3,395 hours per year over 1940-2025.
What is the biggest single-day snowfall in Aiken?
The heaviest 24-hour snowfall measured in Aiken between 1940 and 2025 was 10 February 1973, with 21.1 cm.
Are there tropical nights in Aiken?
Yes: Aiken has on average 100 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Aiken?
In Aiken, between 1940 and 2025, the highest apparent temperature reached 45.7 °C on 21 August 1983, and the lowest was -25.4 °C on 21 January 1985.
Compare Aiken with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Aiken