Bastos climate — normals and trends
Bastos (Brazil) has a tropical savanna climate (Aw) under the Köppen-Geiger classification. Its mean annual temperature is 22.9 °C and it receives 1,292 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 (25.0 °C on average) and the coldest is June (19.3 °C). Rainfall peaks in January.
Bastos averages 0 frost days, 121 hot days (≥ 30 °C) and 143 rainy days per year.
Bastos has warmed by +2.1 °C between 1940 and 2025, or +0.25 °C per decade. This trend is statistically significant.
The hottest day of the period reached 41.6 °C (on 17 October 2014) and the coldest 0.7 °C (on 18 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
BastosSão Paulo
- coords
- -21.92°, -50.73°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
22.9°C
Average daily high
28.3°C
Average daily low
18.4°C
Annual rainfall
1,292mm
Sunshine / day
10.0h
Mean relative humidity
71%
Average peak wind
14.0km/h
Seasonal range
5.7°C
Frost days (< 0 °C)
0 d/yr
Hot days (≥ 30 °C)
121 d/yr
Rainy days (≥ 1 mm)
143 d/yr
Annual snowfall
0.0 cm
Average feels-like high
30.7 °C
Average feels-like low
19.0 °C
Average peak gust
31.3 km/h
Tropical nights (≥ 20 °C)
148 d/yr
Solar radiation
18.4 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.1 °C
since 1940
+0.3 °C per decade · r² = 0.65 · 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
41.6 °C
17 October 2014
Coldest day
0.7 °C
18 July 1975
Wettest day
127 mm
18 March 1974
Windiest day
41.3 km/h
15 September 1956
Strongest gust
86.8 km/h
22 September 2025
Hottest feels-like
43.5 °C
9 December 2012
Coldest feels-like
-3.6 °C
18 July 1975
Sunniest day
13.1 h
10 December 2021
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 | 32.8 °C | +3.2 °C | 94 mm | -115 mm |
| Feb | 31.9 °C | +2.3 °C | 129 mm | -58 mm |
| Mar | 32.7 °C | +3.3 °C | 44 mm | -91 mm |
| Apr | 28.5 °C | +0.2 °C | 121 mm | +53 mm |
| May | 27.4 °C | +1.5 °C | 20 mm | -43 mm |
| Jun | 25.2 °C | +0.2 °C | 41 mm | -5 mm |
| Jul | 26.0 °C | +0.5 °C | 1 mm | -30 mm |
| Aug | 28.5 °C | +0.5 °C | 3 mm | -28 mm |
| Sep | 32.7 °C | +3.1 °C | 11 mm | -57 mm |
| Oct | 30.1 °C | +0.4 °C | 75 mm | -49 mm |
| Nov | 29.9 °C | +0.2 °C | 95 mm | -42 mm |
| Dec | 31.3 °C | +1.8 °C | 208 mm | +10 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 Bastos?
Bastos has a tropical savanna climate (Köppen Aw). Over 1940-2025, the average annual temperature is 22.9 °C and it receives 1,292 mm of precipitation per year.
What is the hottest day ever recorded in Bastos?
The hottest day measured in Bastos between 1940 and 2025 was 17 October 2014, reaching 41.6 °C.
What is the coldest day in Bastos?
The coldest day measured in Bastos between 1940 and 2025 was 18 July 1975, at 0.7 °C.
Does it snow in Bastos?
Almost never: Bastos sees virtually no snow, with about 0 frost days per year.
Has the climate of Bastos warmed?
Yes: Bastos warmed by +2.1 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Bastos?
The wettest day measured in Bastos between 1940 and 2025 was 18 March 1974, with 127 mm of rain in 24 hours.
What was the windiest day in Bastos?
The windiest day measured in Bastos between 1940 and 2025 was 15 September 1956, with winds reaching 41.3 km/h.
What is the warmest month in Bastos?
The warmest month in Bastos is January (25.0 °C on average); the coldest is June (19.3 °C).
How much does it rain in Bastos?
Bastos receives on average 1,292 mm of precipitation per year, spread over about 143 rainy days.
Is it sunny in Bastos?
Bastos gets on average 10.0 hours of sunshine per day, roughly 3,650 hours per year over 1940-2025.
Are there tropical nights in Bastos?
Yes: Bastos has on average 148 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Bastos?
In Bastos, between 1940 and 2025, the highest apparent temperature reached 43.5 °C on 9 December 2012, and the lowest was -3.6 °C on 18 July 1975.
Compare Bastos with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Bastos