Changshu climate — normals and trends
Changshu (China) has a humid subtropical climate (Cfa) under the Köppen-Geiger classification. Its mean annual temperature is 16.1 °C and it receives 1,298 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 (28.3 °C on average) and the coldest is January (3.5 °C). Rainfall peaks in June.
Changshu averages 37 frost days, 62 hot days (≥ 30 °C) and 122 rainy days per year.
Changshu has warmed by +1.6 °C between 1940 and 2025, or +0.19 °C per decade. This trend is statistically significant.
The number of frost days there went from about 48 to 26 per year over the period.
The hottest day of the period reached 42.3 °C (on 24 July 2017) and the coldest -14.8 °C (on 17 January 1945).
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
ChangshuJiangsu
- coords
- 31.65°, 120.74°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
16.1°C
Average daily high
20.1°C
Average daily low
12.7°C
Annual rainfall
1,298mm
Sunshine / day
7.8h
Mean relative humidity
77%
Average peak wind
16.5km/h
Seasonal range
24.8°C
Frost days (< 0 °C)
37 d/yr
Hot days (≥ 30 °C)
62 d/yr
Rainy days (≥ 1 mm)
122 d/yr
Annual snowfall
8.3 cm
Average feels-like high
20.3 °C
Average feels-like low
12.1 °C
Average peak gust
33.0 km/h
Tropical nights (≥ 20 °C)
103 d/yr
Solar radiation
14.3 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.6 °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
42.3 °C
24 July 2017
Coldest day
-14.8 °C
17 January 1945
Wettest day
197 mm
26 July 1949
Windiest day
56.3 km/h
22 August 1951
Strongest gust
110.2 km/h
22 August 1951
Hottest feels-like
48.3 °C
26 July 2016
Coldest feels-like
-19.6 °C
17 January 1945
Snowiest day
24.0 cm
18 January 1984
Sunniest day
14.0 h
19 June 1940
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 | 10.8 °C | +3.3 °C | 10 mm | -35 mm |
| Feb | 9.8 °C | +0.8 °C | 14 mm | -43 mm |
| Mar | 16.9 °C | +3.3 °C | 62 mm | -25 mm |
| Apr | 24.8 °C | +5.2 °C | 39 mm | -68 mm |
| May | 27.0 °C | +2.5 °C | 145 mm | +12 mm |
| Jun | 29.1 °C | +1.2 °C | 276 mm | +31 mm |
| Jul | 33.3 °C | +1.6 °C | 217 mm | +8 mm |
| Aug | 34.1 °C | +2.6 °C | 154 mm | +6 mm |
| Sep | 30.6 °C | +3.4 °C | 215 mm | +88 mm |
| Oct | 24.5 °C | +2.3 °C | 51 mm | -5 mm |
| Nov | 17.8 °C | +1.3 °C | 8 mm | -41 mm |
| Dec | 13.2 °C | +3.0 °C | 6 mm | -30 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 Changshu?
Changshu has a humid subtropical climate (Köppen Cfa). Over 1940-2025, the average annual temperature is 16.1 °C and it receives 1,298 mm of precipitation per year.
What is the hottest day ever recorded in Changshu?
The hottest day measured in Changshu between 1940 and 2025 was 24 July 2017, reaching 42.3 °C.
What is the coldest day in Changshu?
The coldest day measured in Changshu between 1940 and 2025 was 17 January 1945, at -14.8 °C.
Does it snow in Changshu?
Yes. Changshu gets on average 8.3 cm of snow per year and has around 37 frost days.
Has the climate of Changshu warmed?
Yes: Changshu warmed by +1.6 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Changshu?
The wettest day measured in Changshu between 1940 and 2025 was 26 July 1949, with 197 mm of rain in 24 hours.
What was the windiest day in Changshu?
The windiest day measured in Changshu between 1940 and 2025 was 22 August 1951, with winds reaching 56.3 km/h.
What is the warmest month in Changshu?
The warmest month in Changshu is July (28.3 °C on average); the coldest is January (3.5 °C).
How much does it rain in Changshu?
Changshu receives on average 1,298 mm of precipitation per year, spread over about 122 rainy days.
Is it sunny in Changshu?
Changshu gets on average 7.8 hours of sunshine per day, roughly 2,847 hours per year over 1940-2025.
What is the biggest single-day snowfall in Changshu?
The heaviest 24-hour snowfall measured in Changshu between 1940 and 2025 was 18 January 1984, with 24.0 cm.
Are there tropical nights in Changshu?
Yes: Changshu has on average 103 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Changshu?
In Changshu, between 1940 and 2025, the highest apparent temperature reached 48.3 °C on 26 July 2016, and the lowest was -19.6 °C on 17 January 1945.
Compare Changshu with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Changshu