La Unión climate — normals and trends
La Unión (Chile) has a warm-summer mediterranean climate (Csb) under the Köppen-Geiger classification. Its mean annual temperature is 10.9 °C and it receives 1,507 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 January (15.7 °C on average) and the coldest is July (6.6 °C). Rainfall peaks in June.
La Unión averages 22 frost days, 1 hot days (≥ 30 °C) and 150 rainy days per year.
La Unión has warmed by +0.8 °C between 1940 and 2025, or +0.09 °C per decade. This trend is statistically significant.
The number of frost days there went from about 19 to 25 per year over the period.
The hottest day of the period reached 36.7 °C (on 3 February 2019) and the coldest -8.2 °C (on 3 July 1953).
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
La UniónLos Ríos Region
- coords
- -40.29°, -73.08°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
10.9°C
Average daily high
15.6°C
Average daily low
6.4°C
Annual rainfall
1,507mm
Sunshine / day
8.9h
Mean relative humidity
80%
Average peak wind
15.9km/h
Seasonal range
9.1°C
Frost days (< 0 °C)
22 d/yr
Hot days (≥ 30 °C)
1 d/yr
Rainy days (≥ 1 mm)
150 d/yr
Annual snowfall
1.3 cm
Average feels-like high
14.1 °C
Average feels-like low
4.1 °C
Average peak gust
37.2 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
14.4 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+0.8 °C
since 1940
+0.1 °C per decade · r² = 0.24 · 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
36.7 °C
3 February 2019
Coldest day
-8.2 °C
3 July 1953
Wettest day
115 mm
2 June 2000
Windiest day
45.8 km/h
3 August 2005
Strongest gust
114.1 km/h
23 May 1985
Hottest feels-like
38.9 °C
25 January 1944
Coldest feels-like
-13.0 °C
3 July 1953
Snowiest day
8.8 cm
28 August 2020
Sunniest day
14.7 h
9 December 1940
Normals computed over complete calendar years 1940–2025.
A specific year
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Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 23.9 °C | +2.4 °C | 25 mm | -18 mm |
| Feb | 22.2 °C | +0.4 °C | 38 mm | -1 mm |
| Mar | 19.8 °C | +0.3 °C | 59 mm | -3 mm |
| Apr | 15.7 °C | 0.0 °C | 170 mm | +54 mm |
| May | 12.7 °C | +0.1 °C | 161 mm | -50 mm |
| Jun | 10.1 °C | -0.3 °C | 177 mm | -64 mm |
| Jul | 11.2 °C | +1.2 °C | 202 mm | -30 mm |
| Aug | 13.0 °C | +1.9 °C | 108 mm | -88 mm |
| Sep | 14.2 °C | +1.2 °C | 183 mm | +49 mm |
| Oct | 16.2 °C | +1.2 °C | 101 mm | -6 mm |
| Nov | 19.7 °C | +2.5 °C | 36 mm | -34 mm |
| Dec | 21.0 °C | +1.3 °C | 40 mm | -18 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 La Unión?
La Unión has a warm-summer mediterranean climate (Köppen Csb). Over 1940-2025, the average annual temperature is 10.9 °C and it receives 1,507 mm of precipitation per year.
What is the hottest day ever recorded in La Unión?
The hottest day measured in La Unión between 1940 and 2025 was 3 February 2019, reaching 36.7 °C.
What is the coldest day in La Unión?
The coldest day measured in La Unión between 1940 and 2025 was 3 July 1953, at -8.2 °C.
Does it snow in La Unión?
Yes. La Unión gets on average 1.3 cm of snow per year and has around 22 frost days.
Has the climate of La Unión warmed?
Yes: La Unión warmed by +0.8 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in La Unión?
The wettest day measured in La Unión between 1940 and 2025 was 2 June 2000, with 115 mm of rain in 24 hours.
What was the windiest day in La Unión?
The windiest day measured in La Unión between 1940 and 2025 was 3 August 2005, with winds reaching 45.8 km/h.
What is the warmest month in La Unión?
The warmest month in La Unión is January (15.7 °C on average); the coldest is July (6.6 °C).
How much does it rain in La Unión?
La Unión receives on average 1,507 mm of precipitation per year, spread over about 150 rainy days.
Is it sunny in La Unión?
La Unión 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 La Unión?
The heaviest 24-hour snowfall measured in La Unión between 1940 and 2025 was 28 August 2020, with 8.8 cm.
Are there tropical nights in La Unión?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in La Unión.
What was the most extreme apparent temperature in La Unión?
In La Unión, between 1940 and 2025, the highest apparent temperature reached 38.9 °C on 25 January 1944, and the lowest was -13.0 °C on 3 July 1953.
Compare La Unión with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around La Unión