Climate averages 1991–2020
Porto Velho weather
in December.
A hot, very wet month: the joint 6th warmest and the 9th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a hot month in Porto Velho: daytime highs average 29.7°C and nights cool to about 23.5°C. By daytime temperature it is the joint 6th warmest of the 12 months.
Expect about 298 mm of rain on roughly 29 days, which makes December a very wet month (the 9th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 37 min on an average December day.
The nearest other city in this atlas is Ariquemes (159 km away). In December its highs average 29.8°C, about as warm as Porto Velho, with 246 mm of rain.
Among the 448 cities listed in Brazil, Porto Velho ranks joint 120th of 448 for the warmest December highs and joint 436th of 448 for the driest December (rainfall, lowest first). The mean December high of those 448 cities is 28.5°C; Porto Velho is 1.2°C warmer than that mean.
From December to January, average highs fall by 0.2°C to 29.6°C, and monthly rainfall rises from 298 mm to 303 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
Porto Velho climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 29.6°C23.4°C | 23.4°C | 303 | 28.6 | 12.613 h |
| February | 29.4°C23.3°C | 23.3°C | 318 | 27.0 | 12.412 h |
| March | 29.3°C23.4°C | 23.4°C | 328 | 29.4 | 12.212 h |
| April | 29.2°C23.3°C | 23.3°C | 228 | 26.4 | 11.912 h |
| May | 29.1°C22.9°C | 22.9°C | 133 | 21.4 | 11.712 h |
| June | 29.7°C22.3°C | 22.3°C | 43 | 9.5 | 11.612 h |
| July | 31.3°C21.9°C | 21.9°C | 22 | 4.7 | 11.712 h |
| August | 33.0°C22.9°C | 22.9°C | 42 | 7.5 | 11.812 h |
| September | 32.6°C23.8°C | 23.8°C | 103 | 16.7 | 12.012 h |
| October | 31.7°C23.9°C | 23.9°C | 178 | 23.2 | 12.312 h |
| November | 30.3°C23.7°C | 23.7°C | 245 | 26.2 | 12.513 h |
| December, selected | 29.7°C23.5°C | 23.5°C | 298 | 28.7 | 12.613 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
- Ariquemes in DecemberBrazil · 159 kmHigh 29.8°C · Low 22.9°C · 246 mm rain
- Ji Paraná in DecemberBrazil · 319 kmHigh 29.5°C · Low 23.0°C · 248 mm rain
- Riberalta in DecemberBolivia · 343 kmHigh 29.8°C · Low 23.5°C · 262 mm rain
- Cacoal in DecemberBrazil · 401 kmHigh 29.4°C · Low 22.8°C · 284 mm rain
- Rio Branco in DecemberBrazil · 449 kmHigh 29.5°C · Low 23.0°C · 246 mm rain
- Coari in DecemberBrazil · 527 kmHigh 29.3°C · Low 24.2°C · 256 mm rain
- Vilhena in DecemberBrazil · 603 kmHigh 27.7°C · Low 21.1°C · 259 mm rain
- Tefé in DecemberBrazil · 606 kmHigh 29.5°C · Low 23.7°C · 268 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 Porto Velho) is explained once on the Porto Velho year overview and on the Sources, method and limits page.