Clinton climate — normals and trends
Clinton (United States) has a hot-summer humid continental climate (Dfa) under the Köppen-Geiger classification. Its mean annual temperature is 9.8 °C and it receives 921 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 (23.6 °C on average) and the coldest is January (-6.2 °C). Rainfall peaks in May.
Clinton averages 122 frost days, 29 hot days (≥ 30 °C) and 110 rainy days per year.
Clinton has warmed by +1.9 °C between 1940 and 2025, or +0.23 °C per decade. This trend is statistically significant.
The number of frost days there went from about 133 to 111 per year over the period.
The hottest day of the period reached 39.4 °C (on 17 August 1988) and the coldest -34.7 °C (on 3 February 1996).
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
ClintonIowa
- coords
- 41.84°, -90.19°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
9.8°C
Average daily high
14.7°C
Average daily low
5.1°C
Annual rainfall
921mm
Sunshine / day
8.8h
Mean relative humidity
71%
Average peak wind
19.6km/h
Seasonal range
29.8°C
Frost days (< 0 °C)
122 d/yr
Hot days (≥ 30 °C)
29 d/yr
Rainy days (≥ 1 mm)
110 d/yr
Annual snowfall
67.0 cm
Average feels-like high
12.7 °C
Average feels-like low
2.2 °C
Average peak gust
37.6 km/h
Tropical nights (≥ 20 °C)
30 d/yr
Solar radiation
15.0 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.9 °C
since 1940
+0.2 °C per decade · r² = 0.33 · 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
39.4 °C
17 August 1988
Coldest day
-34.7 °C
3 February 1996
Wettest day
94 mm
13 September 1961
Windiest day
54.3 km/h
11 November 1940
Strongest gust
104.8 km/h
15 December 2021
Hottest feels-like
43.8 °C
13 July 1995
Coldest feels-like
-40.2 °C
31 January 2019
Snowiest day
23.8 cm
15 December 1987
Sunniest day
14.4 h
26 June 2012
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 | -1.0 °C | +1.1 °C | 36 mm | -9 mm |
| Feb | 0.6 °C | 0.0 °C | 18 mm | -24 mm |
| Mar | 13.1 °C | +5.4 °C | 115 mm | +40 mm |
| Apr | 16.6 °C | +1.2 °C | 105 mm | +2 mm |
| May | 22.1 °C | +0.6 °C | 82 mm | -27 mm |
| Jun | 28.8 °C | +2.2 °C | 133 mm | +28 mm |
| Jul | 29.5 °C | +1.1 °C | 120 mm | +31 mm |
| Aug | 27.4 °C | -0.1 °C | 76 mm | -8 mm |
| Sep | 27.3 °C | +3.5 °C | 23 mm | -62 mm |
| Oct | 20.7 °C | +3.4 °C | 37 mm | -35 mm |
| Nov | 10.1 °C | +1.7 °C | 51 mm | -9 mm |
| Dec | 0.4 °C | -0.6 °C | 48 mm | -3 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 Clinton?
Clinton has a hot-summer humid continental climate (Köppen Dfa). Over 1940-2025, the average annual temperature is 9.8 °C and it receives 921 mm of precipitation per year.
What is the hottest day ever recorded in Clinton?
The hottest day measured in Clinton between 1940 and 2025 was 17 August 1988, reaching 39.4 °C.
What is the coldest day in Clinton?
The coldest day measured in Clinton between 1940 and 2025 was 3 February 1996, at -34.7 °C.
Does it snow in Clinton?
Yes. Clinton gets on average 67.0 cm of snow per year and has around 122 frost days.
Has the climate of Clinton warmed?
Yes: Clinton warmed by +1.9 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Clinton?
The wettest day measured in Clinton between 1940 and 2025 was 13 September 1961, with 94 mm of rain in 24 hours.
What was the windiest day in Clinton?
The windiest day measured in Clinton between 1940 and 2025 was 11 November 1940, with winds reaching 54.3 km/h.
What is the warmest month in Clinton?
The warmest month in Clinton is July (23.6 °C on average); the coldest is January (-6.2 °C).
How much does it rain in Clinton?
Clinton receives on average 921 mm of precipitation per year, spread over about 110 rainy days.
Is it sunny in Clinton?
Clinton gets on average 8.8 hours of sunshine per day, roughly 3,212 hours per year over 1940-2025.
What is the biggest single-day snowfall in Clinton?
The heaviest 24-hour snowfall measured in Clinton between 1940 and 2025 was 15 December 1987, with 23.8 cm.
Are there tropical nights in Clinton?
Yes: Clinton has on average 30 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Clinton?
In Clinton, between 1940 and 2025, the highest apparent temperature reached 43.8 °C on 13 July 1995, and the lowest was -40.2 °C on 31 January 2019.
Compare Clinton with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Clinton