Climate averages 1991–2020
Rio Branco weather
in May.
A hot, moderately wet month: the coolest and the joint 4th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
May is a hot month in Rio Branco: daytime highs average 28.4°C and nights cool to about 21.6°C. By daytime temperature it is the coolest month of the year.
Expect about 76 mm of rain on roughly 15 days, which makes May a moderately wet month (the joint 4th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 11 h 40 min on an average May day.
The nearest other city in this atlas is Riberalta (224 km away). In May its highs average 28.5°C, about as warm as Rio Branco, with 81 mm of rain.
Among the 448 cities listed in Brazil, Rio Branco ranks joint 98th of 448 for the warmest May highs and joint 247th of 448 for the driest May (rainfall, lowest first). The mean May high of those 448 cities is 25.3°C; Rio Branco is 3.1°C warmer than that mean.
From May to June, average highs rise by 0.5°C to 28.9°C, and monthly rainfall falls from 76 mm to 30 mm.
The annual picture
May 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
Rio Branco climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 29.4°C22.9°C | 22.9°C | 255 | 27.6 | 12.613 h |
| February | 29.2°C22.8°C | 22.8°C | 243 | 25.3 | 12.412 h |
| March | 29.2°C22.8°C | 22.8°C | 249 | 27.2 | 12.212 h |
| April | 28.9°C22.4°C | 22.4°C | 160 | 22.7 | 11.912 h |
| May, selected | 28.4°C21.6°C | 21.6°C | 76 | 15.4 | 11.712 h |
| June | 28.9°C20.9°C | 20.9°C | 30 | 6.8 | 11.612 h |
| July | 30.4°C20.4°C | 20.4°C | 21 | 4.2 | 11.612 h |
| August | 32.1°C21.4°C | 21.4°C | 38 | 6.3 | 11.812 h |
| September | 32.4°C22.7°C | 22.7°C | 76 | 11.9 | 12.012 h |
| October | 31.5°C23.0°C | 23.0°C | 137 | 19.5 | 12.312 h |
| November | 30.1°C22.9°C | 22.9°C | 199 | 22.9 | 12.613 h |
| December | 29.5°C23.0°C | 23.0°C | 246 | 26.3 | 12.713 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
May in nearby cities
- Riberalta in MayBolivia · 224 kmHigh 28.5°C · Low 22.0°C · 81 mm rain
- Puerto Maldonado in MayPeru · 328 kmHigh 27.7°C · Low 21.1°C · 88 mm rain
- Porto Velho in MayBrazil · 449 kmHigh 29.1°C · Low 22.9°C · 133 mm rain
- Ariquemes in MayBrazil · 522 kmHigh 29.3°C · Low 22.2°C · 91 mm rain
- Cruzeiro do Sul in MayBrazil · 595 kmHigh 28.3°C · Low 22.0°C · 134 mm rain
- Cusco in MayPeru · 601 kmHigh 15.3°C · Low 6.5°C · 24 mm rain
- Trinidad in MayBolivia · 626 kmHigh 27.6°C · Low 20.9°C · 84 mm rain
- Ji Paraná in MayBrazil · 649 kmHigh 29.2°C · Low 21.8°C · 78 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 Rio Branco) is explained once on the Rio Branco year overview and on the Sources, method and limits page.