Guaíba in Summer
In summer (December, January and February), Guaíba sees average daytime highs around 30°C and overnight lows near 20°C, with 387 mm of rain over about 39 wet days across the season. It is the warmest season of the year and the 2nd-wettest season.
Across summer, daytime highs hold fairly steady around 30°C. The sky is clear or mostly clear about 31% of the time across summer, and the air most often feels muggy.
Summer is Guaíba's weakest season of the year to visit on our travel score. For the whole year in context, see Guaíba's year-round climate.
- Avg daytime high
- 30°C
- warmest season of the year
- Avg overnight low
- 20°C
- Rainfall
- 387 mm
- 39 wet days
- Avg wind
- 11 km/h
- Travel score
- 4.8
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in Guaíba in Summer
Across summer, daytime highs hold fairly steady around 30°C.
A typical summer day in Guaíba reaches about 30°C and drops to 20°C overnight. The warmest of the three months is January, the coolest December.
How summer really feels in Guaíba
Once humidity and wind are folded in, summer brings about 10 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.
Guaíba 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° / 21° | 137 | 14.1 | 13.7 | 4.6 |
| Feb | 30° / 21° | 126 | 13.3 | 13.1 | 4.6 |
| Mar | 28° / 20° | 112 | 11.9 | 12.2 | 5.7 |
| Apr | 26° / 17° | 106 | 9.2 | 11.3 | 6.8 |
| May | 22° / 13° | 107 | 9.2 | 10.5 | 6.7 |
| Jun | 20° / 11° | 113 | 9.2 | 10.1 | 6.2 |
| Jul | 19° / 10° | 140 | 10 | 10.3 | 6.1 |
| Aug | 21° / 11° | 120 | 10.2 | 10.9 | 6.5 |
| Sep | 22° / 13° | 146 | 11.1 | 11.8 | 6.4 |
| Oct | 24° / 16° | 170 | 12.5 | 12.7 | 6.4 |
| Nov | 27° / 17° | 123 | 10.8 | 13.5 | 6.4 |
| Dec | 29° / 20° | 125 | 11.7 | 13.9 | 5.2 |
Cloud cover in Summer
The sky is clear or mostly clear about 31% of the time across summer.
Chance of precipitation in Summer
Guaíba gets around 387 mm of rain over 39 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 11 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 13 h 48 min in early December to 12 h 42 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 6.2 kWh/m².
Is summer a good time to visit Guaíba?
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 reasonable time to visit Guaíba for sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Guaíba in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Guaíba sees daytime highs around 30°C and nights near 20°C. Pack light clothes, rain gear and sun protection. About 39 days see rain.
Sea temperature near Guaíba in Summer
The nearest coast averages about 25°C across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea at the nearest coast (about 35 km away) is warmest in February at about 26°C and coldest in July near 15°C.
It's comfortable for a long swim from Oct 23 to May 10 — about 6.6 months when the water holds above 20°C.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 26 | 26 | 25 | 23 | 19 | 17 | 15 | 16 | 17 | 20 | 22 | 24 |
| Comfort | Warm | Warm | Warm | Refreshing | Cool | Cool | Cool | Cool | Cool | Cool | Refreshing | Warm |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 26 | Warm |
| Feb | 26 | Warm |
| Mar | 25 | Warm |
| Apr | 23 | Refreshing |
| May | 19 | Cool |
| Jun | 17 | Cool |
| Jul | 15 | Cool |
| Aug | 16 | Cool |
| Sep | 17 | Cool |
| Oct | 20 | Cool |
| Nov | 22 | Refreshing |
| Dec | 24 | Warm |
UV index in Guaíba in Summer
Clear-sky midday UV across summer averages around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Guaíba peaks around January 15 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 19 at about 3 (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) | 13 | 12 | 10 | 7 | 4 | 3 | 4 | 5 | 8 | 8 | 11 | 12 |
| Level | Extreme | Extreme | Very high | Very high | Moderate | Moderate | Moderate | Moderate | Very high | Very high | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 13 | Extreme |
| Feb | 12 | Extreme |
| Mar | 10 | Very high |
| Apr | 7 | Very high |
| May | 4 | Moderate |
| Jun | 3 | Moderate |
| Jul | 4 | Moderate |
| Aug | 5 | Moderate |
| Sep | 8 | Very high |
| Oct | 8 | Very high |
| Nov | 11 | Extreme |
| Dec | 12 | Extreme |
Air quality in Guaíba 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 Guaíba is worst in August — around 27 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (December, 13 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 | 15 | 18 | 21 | 23 | 25 | 27 | 23 | 16 | 15 | 13 |
| Level | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 13 | Moderate |
| Feb | 13 | Moderate |
| Mar | 15 | Moderate |
| Apr | 18 | Moderate |
| May | 21 | Moderate |
| Jun | 23 | Moderate |
| Jul | 25 | Moderate |
| Aug | 27 | Moderate |
| Sep | 23 | Moderate |
| Oct | 16 | Moderate |
| Nov | 15 | Moderate |
| Dec | 13 | Moderate |
Where is Guaíba?
Guaíba sits at 30.1°S, 51.3°W, 22 m above sea level, in Brazil. The nearest listed city is Porto Alegre, 13 km away.
Topography around Guaíba
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Guaíba.
Within 3 km, the terrain around Guaíba has only modest variations in elevation — a maximum elevation change of 126 m around an average of 15 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 293 m; within 80 km, large variations in elevation — a maximum elevation change of 800 m.
The land around Guaíba is covered by artificial surfaces (33%), water (24%) and trees (21%) within 3 km, water (25%), trees (23%) and cropland (22%) within 16 km, and trees (41%) and grassland (20%) 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 Guaíba (-30.1139°, -51.325°, elevation 22 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.