Cacoal climate — normals and trends
Cacoal (Brazil) has a tropical savanna climate (Aw) under the Köppen-Geiger classification. Its mean annual temperature is 25.2 °C and it receives 1,876 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 September (26.7 °C on average) and the coldest is May (24.3 °C). Rainfall peaks in January.
Cacoal averages 0 frost days, 207 hot days (≥ 30 °C) and 223 rainy days per year.
Cacoal has warmed by +1.0 °C between 1940 and 2025, or +0.11 °C per decade. This trend is statistically significant.
The hottest day of the period reached 40.9 °C (on 17 September 1961) and the coldest 9.8 °C (on 19 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
CacoalRondônia
- coords
- -11.44°, -61.45°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
25.2°C
Average daily high
30.5°C
Average daily low
21.5°C
Annual rainfall
1,876mm
Sunshine / day
9.8h
Mean relative humidity
81%
Average peak wind
9.0km/h
Seasonal range
2.4°C
Frost days (< 0 °C)
0 d/yr
Hot days (≥ 30 °C)
207 d/yr
Rainy days (≥ 1 mm)
223 d/yr
Annual snowfall
0.0 cm
Average feels-like high
35.6 °C
Average feels-like low
24.8 °C
Average peak gust
25.9 km/h
Tropical nights (≥ 20 °C)
311 d/yr
Solar radiation
18.4 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.0 °C
since 1940
+0.1 °C per decade · r² = 0.36 · 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
40.9 °C
17 September 1961
Coldest day
9.8 °C
19 July 1975
Wettest day
136 mm
20 January 1965
Windiest day
27.0 km/h
17 July 1975
Strongest gust
63.4 km/h
21 August 2016
Hottest feels-like
44.4 °C
23 October 2015
Coldest feels-like
5.1 °C
18 July 1975
Sunniest day
12.6 h
17 January 1942
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 | 29.0 °C | -0.2 °C | 279 mm | -16 mm |
| Feb | 29.3 °C | +0.2 °C | 248 mm | -35 mm |
| Mar | 29.9 °C | +0.6 °C | 202 mm | -60 mm |
| Apr | 30.0 °C | +0.6 °C | 183 mm | +26 mm |
| May | 30.3 °C | +1.1 °C | 66 mm | -10 mm |
| Jun | 30.4 °C | +0.2 °C | 33 mm | +12 mm |
| Jul | 31.6 °C | -0.1 °C | 0 mm | -13 mm |
| Aug | 33.5 °C | +0.3 °C | 4 mm | -26 mm |
| Sep | 33.9 °C | +0.9 °C | 61 mm | -25 mm |
| Oct | 32.3 °C | +0.6 °C | 146 mm | -15 mm |
| Nov | 31.7 °C | +1.3 °C | 213 mm | -10 mm |
| Dec | 29.1 °C | -0.3 °C | 403 mm | +132 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 Cacoal?
Cacoal has a tropical savanna climate (Köppen Aw). Over 1940-2025, the average annual temperature is 25.2 °C and it receives 1,876 mm of precipitation per year.
What is the hottest day ever recorded in Cacoal?
The hottest day measured in Cacoal between 1940 and 2025 was 17 September 1961, reaching 40.9 °C.
What is the coldest day in Cacoal?
The coldest day measured in Cacoal between 1940 and 2025 was 19 July 1975, at 9.8 °C.
Does it snow in Cacoal?
Almost never: Cacoal sees virtually no snow, with about 0 frost days per year.
Has the climate of Cacoal warmed?
Yes: Cacoal warmed by +1.0 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Cacoal?
The wettest day measured in Cacoal between 1940 and 2025 was 20 January 1965, with 136 mm of rain in 24 hours.
What was the windiest day in Cacoal?
The windiest day measured in Cacoal between 1940 and 2025 was 17 July 1975, with winds reaching 27.0 km/h.
What is the warmest month in Cacoal?
The warmest month in Cacoal is September (26.7 °C on average); the coldest is May (24.3 °C).
How much does it rain in Cacoal?
Cacoal receives on average 1,876 mm of precipitation per year, spread over about 223 rainy days.
Is it sunny in Cacoal?
Cacoal gets on average 9.8 hours of sunshine per day, roughly 3,577 hours per year over 1940-2025.
Are there tropical nights in Cacoal?
Yes: Cacoal has on average 311 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Cacoal?
In Cacoal, between 1940 and 2025, the highest apparent temperature reached 44.4 °C on 23 October 2015, and the lowest was 5.1 °C on 18 July 1975.
Compare Cacoal with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Cacoal