Rio Branco in Summer
In summer (December, January and February), Rio Branco sees average daytime highs around 30°C and overnight lows near 23°C, with 741 mm of rain over about 79 wet days across the season. It is the 3rd-warmest season and the wettest season of the year.
Across summer, daytime highs hold fairly steady around 30°C. The sky is clear or mostly clear about 1% of the time across summer, and the air most often feels oppressive.
Summer is Rio Branco's weakest season of the year to visit on our travel score. For the whole year in context, see Rio Branco's year-round climate.
- Avg daytime high
- 30°C
- 3rd-warmest season
- Avg overnight low
- 23°C
- Rainfall
- 741 mm
- 79 wet days
- Avg wind
- 6 km/h
- Travel score
- 2.8
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in Rio Branco in Summer
Across summer, daytime highs hold fairly steady around 30°C.
A typical summer day in Rio Branco reaches about 30°C and drops to 23°C overnight. The warmest of the three months is December, the coolest February.
How summer really feels in Rio Branco
Once humidity and wind are folded in, summer brings about 90 days that feel above 32°C and 0 that feel at or below 0°C.
The story in summer is heat — humidity pushes the afternoon "feels like" well above the raw temperature.
Rio Branco weather by month
How the three summer months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 30° / 23° | 255 | 27.7 | 12.5 | 2.8 |
| Feb | 30° / 23° | 240 | 25 | 12.3 | 2.8 |
| Mar | 30° / 23° | 249 | 27.2 | 12.1 | 2.8 |
| Apr | 30° / 22° | 160 | 22.8 | 11.8 | 3.2 |
| May | 30° / 21° | 76 | 15.4 | 11.5 | 4.3 |
| Jun | 30° / 20° | 30 | 6.8 | 11.4 | 5.3 |
| Jul | 31° / 20° | 21 | 4.2 | 11.5 | 5.1 |
| Aug | 33° / 20° | 38 | 6.3 | 11.7 | 4.0 |
| Sep | 33° / 22° | 76 | 11.9 | 11.9 | 3.2 |
| Oct | 33° / 23° | 137 | 19.5 | 12.2 | 2.8 |
| Nov | 31° / 23° | 199 | 22.9 | 12.5 | 2.8 |
| Dec | 30° / 23° | 246 | 26.3 | 12.6 | 2.9 |
Cloud cover in Summer
The sky is clear or mostly clear about 1% of the time across summer.
Chance of precipitation in Summer
Rio Branco gets around 741 mm of rain over 79 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 6 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 12 h 30 min in early December to 12 h 12 min by late February. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 4.8 kWh/m².
Hazard calendar for Rio Branco
In summer, Rio Branco overlaps its rainy season season. The full year is below, with each hazard's peak months called out.
Rio Branco's rainy season runs October–April, when most of the year's rain falls.
Is summer a good time to visit Rio Branco?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a weaker month for outdoor sightseeing in Rio Branco.
What to pack for Rio Branco in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Rio Branco sees daytime highs around 30°C and nights near 23°C. Pack light clothes and rain gear. Worth having: sun protection. About 79 days see rain.
UV index in Rio Branco in Summer
Clear-sky midday UV across summer averages around 14 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Rio Branco peaks around January 20 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near September 12 at about 5 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 15 | 15 | 14 | 13 | 11 | 9 | 8 | 7 | 4 | 12 | 13 | 13 |
| Level | Extreme | Extreme | Extreme | Extreme | Extreme | Very high | Very high | High | Moderate | Extreme | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 15 | Extreme |
| Feb | 15 | Extreme |
| Mar | 14 | Extreme |
| Apr | 13 | Extreme |
| May | 11 | Extreme |
| Jun | 9 | Very high |
| Jul | 8 | Very high |
| Aug | 7 | High |
| Sep | 4 | Moderate |
| Oct | 12 | Extreme |
| Nov | 13 | Extreme |
| Dec | 13 | Extreme |
Air quality in Rio Branco in Summer
Average fine-particle pollution (PM2.5) through the year — so you can see where summer falls, not just the annual average.
Air quality in Rio Branco is worst in September — around 100 µg/m³ PM2.5 (unhealthy), about 12.4× the cleanest month (June, 8 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 13 | 13 | 13 | 10 | 8 | 8 | 14 | 65 | 100 | 27 | 13 | 11 |
| Level | Moderate | Moderate | Moderate | Good | Good | Good | Moderate | Unhealthy | Unhealthy | Moderate | Moderate | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 13 | Moderate |
| Feb | 13 | Moderate |
| Mar | 13 | Moderate |
| Apr | 10 | Good |
| May | 8 | Good |
| Jun | 8 | Good |
| Jul | 14 | Moderate |
| Aug | 65 | Unhealthy |
| Sep | 100 | Unhealthy |
| Oct | 27 | Moderate |
| Nov | 13 | Moderate |
| Dec | 11 | Good |
Where is Rio Branco?
Rio Branco sits at 10.0°S, 67.8°W, 153 m above sea level, in Brazil. The nearest listed city is Senador Guiomard, 21 km away.
Topography around Rio Branco
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Rio Branco.
Within 3 km, the terrain around Rio Branco has only modest variations in elevation — a maximum elevation change of 50 m around an average of 142 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 103 m; within 80 km, only modest variations in elevation — a maximum elevation change of 165 m.
The land around Rio Branco is covered by artificial surfaces (54%) and trees (33%) within 3 km, trees (46%) and grassland (46%) within 16 km, and trees (61%) and grassland (38%) within 80 km.
Brazil travel facts
- Travel advisory
- Level 2
- Exercise Increased Caution
- Power plugs
- Type C / N
- 127 / 220 V · 60 Hz
- Prices
- ≈ 46% of US
- price level, 2025
- GDP per capita
- $10,713
- 2025
- Happiness
- 6.6 / 10
- World Happiness, 2025
- Safe drinking water
- 89%
- of population, 2024
- Homicide rate
- 19.3
- per 100k, 2023
- Road deaths
- 16
- per 100k/yr, 2019
- Income group
- Upper middle
- World Bank
- English
- Low
- EF EPI 482
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Rio Branco (-9.9747°, -67.81°, elevation 153 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.