Sun Prairie climate — normals and trends
Sun Prairie (United States) has a hot-summer humid continental climate (Dfa) under the Köppen-Geiger classification. Its mean annual temperature is 8.2 °C and it receives 861 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 (22.2 °C on average) and the coldest is January (-7.7 °C). Rainfall peaks in June.
Sun Prairie averages 137 frost days, 18 hot days (≥ 30 °C) and 113 rainy days per year.
Sun Prairie has warmed by +2.0 °C between 1940 and 2025, or +0.24 °C per decade. This trend is statistically significant.
The number of frost days there went from about 148 to 126 per year over the period.
The hottest day of the period reached 38.3 °C (on 14 July 1995) and the coldest -33.6 °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
Sun PrairieWisconsin
- coords
- 43.18°, -89.21°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
8.2°C
Average daily high
12.9°C
Average daily low
3.6°C
Annual rainfall
861mm
Sunshine / day
8.5h
Mean relative humidity
71%
Average peak wind
19.2km/h
Seasonal range
29.9°C
Frost days (< 0 °C)
137 d/yr
Hot days (≥ 30 °C)
18 d/yr
Rainy days (≥ 1 mm)
113 d/yr
Annual snowfall
90.3 cm
Average feels-like high
10.5 °C
Average feels-like low
0.4 °C
Average peak gust
37.8 km/h
Tropical nights (≥ 20 °C)
16 d/yr
Solar radiation
14.5 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.0 °C
since 1940
+0.2 °C per decade · r² = 0.37 · 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
38.3 °C
14 July 1995
Coldest day
-33.6 °C
3 February 1996
Wettest day
86 mm
13 September 1961
Windiest day
56.8 km/h
30 April 1984
Strongest gust
109.8 km/h
16 December 2021
Hottest feels-like
42.9 °C
13 July 1995
Coldest feels-like
-39.8 °C
10 January 1982
Snowiest day
25.8 cm
20 December 2012
Sunniest day
14.8 h
18 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 | -2.7 °C | +1.0 °C | 3 mm | -37 mm |
| Feb | -1.4 °C | -0.2 °C | 26 mm | -10 mm |
| Mar | 10.8 °C | +5.4 °C | 102 mm | +36 mm |
| Apr | 14.0 °C | +0.8 °C | 81 mm | -12 mm |
| May | 19.2 °C | -0.6 °C | 90 mm | -7 mm |
| Jun | 26.4 °C | +1.3 °C | 117 mm | +19 mm |
| Jul | 27.9 °C | +0.7 °C | 120 mm | +29 mm |
| Aug | 25.5 °C | -0.6 °C | 103 mm | +14 mm |
| Sep | 23.9 °C | +2.0 °C | 40 mm | -43 mm |
| Oct | 17.6 °C | +2.4 °C | 32 mm | -36 mm |
| Nov | 7.7 °C | +1.3 °C | 49 mm | -8 mm |
| Dec | -1.8 °C | -0.9 °C | 45 mm | -1 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 Sun Prairie?
Sun Prairie has a hot-summer humid continental climate (Köppen Dfa). Over 1940-2025, the average annual temperature is 8.2 °C and it receives 861 mm of precipitation per year.
What is the hottest day ever recorded in Sun Prairie?
The hottest day measured in Sun Prairie between 1940 and 2025 was 14 July 1995, reaching 38.3 °C.
What is the coldest day in Sun Prairie?
The coldest day measured in Sun Prairie between 1940 and 2025 was 3 February 1996, at -33.6 °C.
Does it snow in Sun Prairie?
Yes. Sun Prairie gets on average 90.3 cm of snow per year and has around 137 frost days.
Has the climate of Sun Prairie warmed?
Yes: Sun Prairie warmed by +2.0 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Sun Prairie?
The wettest day measured in Sun Prairie between 1940 and 2025 was 13 September 1961, with 86 mm of rain in 24 hours.
What was the windiest day in Sun Prairie?
The windiest day measured in Sun Prairie between 1940 and 2025 was 30 April 1984, with winds reaching 56.8 km/h.
What is the warmest month in Sun Prairie?
The warmest month in Sun Prairie is July (22.2 °C on average); the coldest is January (-7.7 °C).
How much does it rain in Sun Prairie?
Sun Prairie receives on average 861 mm of precipitation per year, spread over about 113 rainy days.
Is it sunny in Sun Prairie?
Sun Prairie gets on average 8.5 hours of sunshine per day, roughly 3,103 hours per year over 1940-2025.
What is the biggest single-day snowfall in Sun Prairie?
The heaviest 24-hour snowfall measured in Sun Prairie between 1940 and 2025 was 20 December 2012, with 25.8 cm.
Are there tropical nights in Sun Prairie?
Yes: Sun Prairie has on average 16 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Sun Prairie?
In Sun Prairie, between 1940 and 2025, the highest apparent temperature reached 42.9 °C on 13 July 1995, and the lowest was -39.8 °C on 10 January 1982.
Compare Sun Prairie with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Sun Prairie