Climate averages 1991–2020
Cacoal weather
in December.
A hot, very wet month: the 7th warmest and the 10th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a hot month in Cacoal: daytime highs average 29.4°C and nights cool to about 22.8°C. By daytime temperature it is the 7th warmest of the 12 months.
Expect about 284 mm of rain on roughly 28 days, which makes December a very wet month (the 10th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 47 min on an average December day.
The nearest other city in this atlas is Ji Paraná (83 km away). In December its highs average 29.5°C, about as warm as Cacoal, with 248 mm of rain.
Among the 448 cities listed in Brazil, Cacoal ranks joint 147th of 448 for the warmest December highs and 427th of 448 for the driest December (rainfall, lowest first). The mean December high of those 448 cities is 28.5°C; Cacoal is 1.0°C warmer than that mean.
From December to January, average highs fall by 0.3°C to 29.1°C, and monthly rainfall rises from 284 mm to 308 mm.
The annual picture
December in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Cacoal climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 29.1°C22.7°C | 22.7°C | 308 | 29.3 | 12.713 h |
| February | 28.9°C22.6°C | 22.6°C | 299 | 26.6 | 12.512 h |
| March | 29.2°C22.6°C | 22.6°C | 270 | 28.2 | 12.212 h |
| April | 29.3°C22.4°C | 22.4°C | 151 | 22.3 | 11.912 h |
| May | 29.3°C21.6°C | 21.6°C | 77 | 13.4 | 11.612 h |
| June | 30.7°C20.5°C | 20.5°C | 17 | 3.5 | 11.511 h |
| July | 32.2°C20.3°C | 20.3°C | 11 | 2.1 | 11.512 h |
| August | 33.7°C21.5°C | 21.5°C | 26 | 4.7 | 11.712 h |
| September | 33.3°C23.0°C | 23.0°C | 90 | 14.1 | 12.012 h |
| October | 32.0°C23.2°C | 23.2°C | 156 | 21.7 | 12.312 h |
| November | 30.3°C22.9°C | 22.9°C | 239 | 24.9 | 12.613 h |
| December, selected | 29.4°C22.8°C | 22.8°C | 284 | 27.9 | 12.813 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
December in nearby cities
- Ji Paraná in DecemberBrazil · 83 kmHigh 29.5°C · Low 23.0°C · 248 mm rain
- Vilhena in DecemberBrazil · 202 kmHigh 27.7°C · Low 21.1°C · 259 mm rain
- Ariquemes in DecemberBrazil · 243 kmHigh 29.8°C · Low 22.9°C · 246 mm rain
- Porto Velho in DecemberBrazil · 401 kmHigh 29.7°C · Low 23.5°C · 298 mm rain
- Riberalta in DecemberBolivia · 505 kmHigh 29.8°C · Low 23.5°C · 262 mm rain
- Trinidad in DecemberBolivia · 531 kmHigh 29.5°C · Low 23.6°C · 298 mm rain
- Tangará da Serra in DecemberBrazil · 556 kmHigh 29.6°C · Low 22.4°C · 209 mm rain
- Lucas do Rio Verde in DecemberBrazil · 628 kmHigh 29.0°C · Low 22.2°C · 232 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Cacoal) is explained once on the Cacoal year overview and on the Sources, method and limits page.