Clemson climate — normals and trends
Clemson (United States) has a humid subtropical climate (Cfa) under the Köppen-Geiger classification. Its mean annual temperature is 15.8 °C and it receives 1,201 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 (25.7 °C on average) and the coldest is January (5.3 °C). Rainfall peaks in March.
Clemson averages 46 frost days, 67 hot days (≥ 30 °C) and 121 rainy days per year.
Clemson has warmed by +1.2 °C between 1940 and 2025, or +0.14 °C per decade. This trend is statistically significant.
The number of frost days there went from about 51 to 41 per year over the period.
The hottest day of the period reached 40.0 °C (on 30 June 2012) and the coldest -20.3 °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
ClemsonSouth Carolina
- coords
- 34.68°, -82.84°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
15.8°C
Average daily high
21.5°C
Average daily low
10.8°C
Annual rainfall
1,201mm
Sunshine / day
9.1h
Mean relative humidity
71%
Average peak wind
12.6km/h
Seasonal range
20.4°C
Frost days (< 0 °C)
46 d/yr
Hot days (≥ 30 °C)
67 d/yr
Rainy days (≥ 1 mm)
121 d/yr
Annual snowfall
10.6 cm
Average feels-like high
21.5 °C
Average feels-like low
9.9 °C
Average peak gust
31.3 km/h
Tropical nights (≥ 20 °C)
72 d/yr
Solar radiation
16.0 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.2 °C
since 1940
+0.1 °C per decade · r² = 0.27 · 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
40.0 °C
30 June 2012
Coldest day
-20.3 °C
21 January 1985
Wettest day
180 mm
26 September 2024
Windiest day
49.6 km/h
27 September 2024
Strongest gust
122.0 km/h
29 October 2020
Hottest feels-like
44.0 °C
21 August 1983
Coldest feels-like
-25.2 °C
21 January 1985
Snowiest day
24.9 cm
3 December 1971
Sunniest day
14.3 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 | 9.2 °C | -1.5 °C | 48 mm | -69 mm |
| Feb | 15.7 °C | +2.8 °C | 99 mm | -13 mm |
| Mar | 19.8 °C | +2.8 °C | 81 mm | -49 mm |
| Apr | 23.4 °C | +1.5 °C | 100 mm | -3 mm |
| May | 24.1 °C | -1.9 °C | 224 mm | +134 mm |
| Jun | 30.1 °C | +0.5 °C | 141 mm | +59 mm |
| Jul | 32.6 °C | +1.5 °C | 60 mm | -34 mm |
| Aug | 27.8 °C | -2.6 °C | 182 mm | +88 mm |
| Sep | 27.2 °C | -0.1 °C | 25 mm | -67 mm |
| Oct | 21.8 °C | -0.4 °C | 83 mm | -0 mm |
| Nov | 18.5 °C | +2.0 °C | 24 mm | -70 mm |
| Dec | 13.0 °C | +1.2 °C | 41 mm | -70 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 Clemson?
Clemson has a humid subtropical climate (Köppen Cfa). Over 1940-2025, the average annual temperature is 15.8 °C and it receives 1,201 mm of precipitation per year.
What is the hottest day ever recorded in Clemson?
The hottest day measured in Clemson between 1940 and 2025 was 30 June 2012, reaching 40.0 °C.
What is the coldest day in Clemson?
The coldest day measured in Clemson between 1940 and 2025 was 21 January 1985, at -20.3 °C.
Does it snow in Clemson?
Yes. Clemson gets on average 10.6 cm of snow per year and has around 46 frost days.
Has the climate of Clemson warmed?
Yes: Clemson warmed by +1.2 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Clemson?
The wettest day measured in Clemson between 1940 and 2025 was 26 September 2024, with 180 mm of rain in 24 hours.
What was the windiest day in Clemson?
The windiest day measured in Clemson between 1940 and 2025 was 27 September 2024, with winds reaching 49.6 km/h.
What is the warmest month in Clemson?
The warmest month in Clemson is July (25.7 °C on average); the coldest is January (5.3 °C).
How much does it rain in Clemson?
Clemson receives on average 1,201 mm of precipitation per year, spread over about 121 rainy days.
Is it sunny in Clemson?
Clemson gets on average 9.1 hours of sunshine per day, roughly 3,322 hours per year over 1940-2025.
What is the biggest single-day snowfall in Clemson?
The heaviest 24-hour snowfall measured in Clemson between 1940 and 2025 was 3 December 1971, with 24.9 cm.
Are there tropical nights in Clemson?
Yes: Clemson has on average 72 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Clemson?
In Clemson, between 1940 and 2025, the highest apparent temperature reached 44.0 °C on 21 August 1983, and the lowest was -25.2 °C on 21 January 1985.
Compare Clemson with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Clemson