Merlo climate — normals and trends
Merlo (Argentina) has a humid subtropical climate (Cfa) under the Köppen-Geiger classification. Its mean annual temperature is 16.7 °C and it receives 916 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 (24.0 °C on average) and the coldest is July (9.8 °C). Rainfall peaks in October.
Merlo averages 6 frost days, 43 hot days (≥ 30 °C) and 90 rainy days per year.
No statistically significant temperature trend emerges for Merlo between 1940 and 2025: over this span, year-to-year swings outweigh the climate signal.
The hottest day of the period reached 42.6 °C (on 11 January 1957) and the coldest -7.8 °C (on 14 June 1967).
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
MerloBuenos Aires
- coords
- -34.67°, -58.73°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
16.7°C
Average daily high
22.0°C
Average daily low
12.0°C
Annual rainfall
916mm
Sunshine / day
9.5h
Mean relative humidity
73%
Average peak wind
18.5km/h
Seasonal range
14.2°C
Frost days (< 0 °C)
6 d/yr
Hot days (≥ 30 °C)
43 d/yr
Rainy days (≥ 1 mm)
90 d/yr
Annual snowfall
0.0 cm
Average feels-like high
21.6 °C
Average feels-like low
10.4 °C
Average peak gust
35.5 km/h
Tropical nights (≥ 20 °C)
29 d/yr
Solar radiation
17.2 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
No clear trend over this period
Over a short window, year-to-year swings outweigh the climate signal. Try 86 years.
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
42.6 °C
11 January 1957
Coldest day
-7.8 °C
14 June 1967
Wettest day
150 mm
3 February 1990
Windiest day
56.7 km/h
16 May 2000
Strongest gust
102.6 km/h
16 May 2000
Hottest feels-like
43.0 °C
1 February 1947
Coldest feels-like
-12.3 °C
14 June 1967
Snowiest day
1.0 cm
9 July 2007
Sunniest day
14.0 h
16 December 2024
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 | 31.1 °C | +1.4 °C | 39 mm | -49 mm |
| Feb | 30.0 °C | +1.5 °C | 103 mm | +12 mm |
| Mar | 26.3 °C | +0.1 °C | 138 mm | +39 mm |
| Apr | 21.6 °C | -0.5 °C | 63 mm | -20 mm |
| May | 19.3 °C | +1.0 °C | 116 mm | +52 mm |
| Jun | 14.4 °C | -0.6 °C | 19 mm | -31 mm |
| Jul | 15.3 °C | +0.7 °C | 20 mm | -33 mm |
| Aug | 16.9 °C | +0.5 °C | 116 mm | +57 mm |
| Sep | 19.1 °C | +0.6 °C | 74 mm | +2 mm |
| Oct | 22.9 °C | +1.6 °C | 77 mm | -23 mm |
| Nov | 24.3 °C | -0.5 °C | 87 mm | +4 mm |
| Dec | 30.6 °C | +2.4 °C | 44 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 Merlo?
Merlo has a humid subtropical climate (Köppen Cfa). Over 1940-2025, the average annual temperature is 16.7 °C and it receives 916 mm of precipitation per year.
What is the hottest day ever recorded in Merlo?
The hottest day measured in Merlo between 1940 and 2025 was 11 January 1957, reaching 42.6 °C.
What is the coldest day in Merlo?
The coldest day measured in Merlo between 1940 and 2025 was 14 June 1967, at -7.8 °C.
Does it snow in Merlo?
Almost never: Merlo sees virtually no snow, with about 6 frost days per year.
Has the climate of Merlo warmed?
Between 1940 and 2025, no statistically significant temperature trend emerges in Merlo.
What is the wettest day in Merlo?
The wettest day measured in Merlo between 1940 and 2025 was 3 February 1990, with 150 mm of rain in 24 hours.
What was the windiest day in Merlo?
The windiest day measured in Merlo between 1940 and 2025 was 16 May 2000, with winds reaching 56.7 km/h.
What is the warmest month in Merlo?
The warmest month in Merlo is January (24.0 °C on average); the coldest is July (9.8 °C).
How much does it rain in Merlo?
Merlo receives on average 916 mm of precipitation per year, spread over about 90 rainy days.
Is it sunny in Merlo?
Merlo gets on average 9.5 hours of sunshine per day, roughly 3,468 hours per year over 1940-2025.
What is the biggest single-day snowfall in Merlo?
The heaviest 24-hour snowfall measured in Merlo between 1940 and 2025 was 9 July 2007, with 1.0 cm.
Are there tropical nights in Merlo?
Yes: Merlo has on average 29 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Merlo?
In Merlo, between 1940 and 2025, the highest apparent temperature reached 43.0 °C on 1 February 1947, and the lowest was -12.3 °C on 14 June 1967.
Compare Merlo with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Merlo