South Milwaukee climate — normals and trends
South Milwaukee (United States) has a hot-summer humid continental climate (Dfa) under the Köppen-Geiger classification. Its mean annual temperature is 8.3 °C and it receives 892 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 August (22.3 °C on average) and the coldest is February (-4.7 °C). Rainfall peaks in April.
South Milwaukee averages 106 frost days, 1 hot days (≥ 30 °C) and 118 rainy days per year.
South Milwaukee has warmed by +1.1 °C between 1940 and 2025, or +0.13 °C per decade. This trend is statistically significant.
The number of frost days there went from about 125 to 87 per year over the period.
The hottest day of the period reached 33.8 °C (on 17 August 1988) and the coldest -28.6 °C (on 23 January 1963).
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
South MilwaukeeWisconsin
- coords
- 42.91°, -87.86°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
8.3°C
Average daily high
10.4°C
Average daily low
6.5°C
Annual rainfall
892mm
Sunshine / day
8.9h
Mean relative humidity
77%
Average peak wind
31.0km/h
Seasonal range
27.0°C
Frost days (< 0 °C)
106 d/yr
Hot days (≥ 30 °C)
1 d/yr
Rainy days (≥ 1 mm)
118 d/yr
Annual snowfall
90.3 cm
Average feels-like high
7.3 °C
Average feels-like low
2.0 °C
Average peak gust
42.7 km/h
Tropical nights (≥ 20 °C)
48 d/yr
Solar radiation
14.7 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.1 °C
since 1940
+0.1 °C per decade · r² = 0.11 · p = 0.002
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
33.8 °C
17 August 1988
Coldest day
-28.6 °C
23 January 1963
Wettest day
97 mm
17 May 2020
Windiest day
76.5 km/h
10 November 1998
Strongest gust
112.7 km/h
11 November 1940
Hottest feels-like
39.4 °C
4 July 2012
Coldest feels-like
-38.0 °C
23 January 1963
Snowiest day
24.4 cm
15 December 1987
Sunniest day
14.8 h
21 June 2003
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 | -1.3 °C | +0.6 °C | 10 mm | -49 mm |
| Feb | -0.3 °C | +1.6 °C | 34 mm | -13 mm |
| Mar | 5.3 °C | +4.0 °C | 102 mm | +29 mm |
| Apr | 7.2 °C | +1.6 °C | 55 mm | -41 mm |
| May | 9.5 °C | -1.5 °C | 97 mm | +15 mm |
| Jun | 17.6 °C | -1.0 °C | 71 mm | -3 mm |
| Jul | 22.2 °C | -1.4 °C | 100 mm | +27 mm |
| Aug | 22.3 °C | -1.7 °C | 67 mm | -10 mm |
| Sep | 20.0 °C | -0.6 °C | 36 mm | -47 mm |
| Oct | 15.8 °C | +1.4 °C | 48 mm | -34 mm |
| Nov | 8.2 °C | +0.9 °C | 66 mm | -13 mm |
| Dec | 0.9 °C | -0.7 °C | 76 mm | +9 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 South Milwaukee?
South Milwaukee has a hot-summer humid continental climate (Köppen Dfa). Over 1940-2025, the average annual temperature is 8.3 °C and it receives 892 mm of precipitation per year.
What is the hottest day ever recorded in South Milwaukee?
The hottest day measured in South Milwaukee between 1940 and 2025 was 17 August 1988, reaching 33.8 °C.
What is the coldest day in South Milwaukee?
The coldest day measured in South Milwaukee between 1940 and 2025 was 23 January 1963, at -28.6 °C.
Does it snow in South Milwaukee?
Yes. South Milwaukee gets on average 90.3 cm of snow per year and has around 106 frost days.
Has the climate of South Milwaukee warmed?
Yes: South Milwaukee warmed by +1.1 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in South Milwaukee?
The wettest day measured in South Milwaukee between 1940 and 2025 was 17 May 2020, with 97 mm of rain in 24 hours.
What was the windiest day in South Milwaukee?
The windiest day measured in South Milwaukee between 1940 and 2025 was 10 November 1998, with winds reaching 76.5 km/h.
What is the warmest month in South Milwaukee?
The warmest month in South Milwaukee is August (22.3 °C on average); the coldest is February (-4.7 °C).
How much does it rain in South Milwaukee?
South Milwaukee receives on average 892 mm of precipitation per year, spread over about 118 rainy days.
Is it sunny in South Milwaukee?
South Milwaukee gets on average 8.9 hours of sunshine per day, roughly 3,249 hours per year over 1940-2025.
What is the biggest single-day snowfall in South Milwaukee?
The heaviest 24-hour snowfall measured in South Milwaukee between 1940 and 2025 was 15 December 1987, with 24.4 cm.
Are there tropical nights in South Milwaukee?
Yes: South Milwaukee has on average 48 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in South Milwaukee?
In South Milwaukee, between 1940 and 2025, the highest apparent temperature reached 39.4 °C on 4 July 2012, and the lowest was -38.0 °C on 23 January 1963.
Compare South Milwaukee with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around South Milwaukee