Rosário climate — normals and trends
Rosário (Brazil) has a tropical monsoon climate (Am) under the Köppen-Geiger classification. Its mean annual temperature is 27.1 °C and it receives 2,167 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 October (28.4 °C on average) and the coldest is March (25.9 °C). Rainfall peaks in March.
Rosário averages 0 frost days, 288 hot days (≥ 30 °C) and 197 rainy days per year.
Rosário has warmed by +1.0 °C between 1940 and 2025, or +0.12 °C per decade. This trend is statistically significant.
The hottest day of the period reached 39.2 °C (on 14 October 1941) and the coldest 19.3 °C (on 27 July 1975).
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
RosárioMaranhão
- coords
- -2.94°, -44.25°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
27.1°C
Average daily high
31.8°C
Average daily low
23.9°C
Annual rainfall
2,167mm
Sunshine / day
10.6h
Mean relative humidity
78%
Average peak wind
13.7km/h
Seasonal range
2.5°C
Frost days (< 0 °C)
0 d/yr
Hot days (≥ 30 °C)
288 d/yr
Rainy days (≥ 1 mm)
197 d/yr
Annual snowfall
0.0 cm
Average feels-like high
36.6 °C
Average feels-like low
27.9 °C
Average peak gust
33.7 km/h
Tropical nights (≥ 20 °C)
364 d/yr
Solar radiation
19.1 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.0 °C
since 1940
+0.1 °C per decade · r² = 0.33 · 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
39.2 °C
14 October 1941
Coldest day
19.3 °C
27 July 1975
Wettest day
233 mm
11 February 2017
Windiest day
26.1 km/h
9 November 1965
Strongest gust
60.1 km/h
6 October 1947
Hottest feels-like
42.9 °C
20 November 2005
Coldest feels-like
19.8 °C
4 July 1974
Sunniest day
12.0 h
2 January 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 | 31.5 °C | +0.6 °C | 350 mm | +64 mm |
| Feb | 30.7 °C | +0.4 °C | 442 mm | +90 mm |
| Mar | 31.0 °C | +1.0 °C | 482 mm | +22 mm |
| Apr | 31.2 °C | +1.1 °C | 315 mm | -111 mm |
| May | 31.3 °C | +0.8 °C | 117 mm | -156 mm |
| Jun | 31.3 °C | +0.7 °C | 38 mm | -67 mm |
| Jul | 32.0 °C | +0.8 °C | 41 mm | -17 mm |
| Aug | 33.3 °C | +0.4 °C | 14 mm | -6 mm |
| Sep | 35.2 °C | +1.2 °C | 2 mm | -12 mm |
| Oct | 35.3 °C | +1.2 °C | 7 mm | -13 mm |
| Nov | 33.8 °C | 0.0 °C | 11 mm | -27 mm |
| Dec | 32.5 °C | -0.2 °C | 78 mm | -38 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 Rosário?
Rosário has a tropical monsoon climate (Köppen Am). Over 1940-2025, the average annual temperature is 27.1 °C and it receives 2,167 mm of precipitation per year.
What is the hottest day ever recorded in Rosário?
The hottest day measured in Rosário between 1940 and 2025 was 14 October 1941, reaching 39.2 °C.
What is the coldest day in Rosário?
The coldest day measured in Rosário between 1940 and 2025 was 27 July 1975, at 19.3 °C.
Does it snow in Rosário?
Almost never: Rosário sees virtually no snow, with about 0 frost days per year.
Has the climate of Rosário warmed?
Yes: Rosário warmed by +1.0 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Rosário?
The wettest day measured in Rosário between 1940 and 2025 was 11 February 2017, with 233 mm of rain in 24 hours.
What was the windiest day in Rosário?
The windiest day measured in Rosário between 1940 and 2025 was 9 November 1965, with winds reaching 26.1 km/h.
What is the warmest month in Rosário?
The warmest month in Rosário is October (28.4 °C on average); the coldest is March (25.9 °C).
How much does it rain in Rosário?
Rosário receives on average 2,167 mm of precipitation per year, spread over about 197 rainy days.
Is it sunny in Rosário?
Rosário gets on average 10.6 hours of sunshine per day, roughly 3,869 hours per year over 1940-2025.
Are there tropical nights in Rosário?
Yes: Rosário has on average 364 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Rosário?
In Rosário, between 1940 and 2025, the highest apparent temperature reached 42.9 °C on 20 November 2005, and the lowest was 19.8 °C on 4 July 1974.
Compare Rosário with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Rosário