Viamão in Summer

In summer (December, January and February), Viamão sees average daytime highs around 29°C and overnight lows near 20°C, with 397 mm of rain over about 41 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 29°C. The sky is clear or mostly clear about 31% of the time across summer, and the air most often feels muggy.

Summer is Viamão's weakest season of the year to visit on our travel score. For the whole year in context, see Viamão's year-round climate.

Avg daytime high
29°C
warmest season of the year
Avg overnight low
20°C
Rainfall
397 mm
41 wet days
Avg wind
11 km/h
Travel score
4.9
weakest season of the year
Months
Dec · Jan · Feb

Temperature in Viamão in Summer

Average highAverage lowShaded bands: 10–90% of days

Across summer, daytime highs hold fairly steady around 29°C.

A typical summer day in Viamão reaches about 29°C and drops to 20°C overnight. The warmest of the three months is January, the coolest December.

10°15°20°25°30°35°DecJanFeb

Viamão 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.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 21°14014.213.74.7
Feb29° / 20°12713.913.14.7
Mar28° / 19°12112.612.25.7
Apr25° / 16°1029.711.36.8
May22° / 13°1069.210.56.7
Jun20° / 11°1129.410.16.2
Jul19° / 10°13610.310.36.1
Aug21° / 11°12210.410.96.5
Sep22° / 13°14711.211.86.3
Oct24° / 15°16912.712.76.4
Nov27° / 17°12210.913.56.4
Dec29° / 19°12912.413.95.4

Cloud cover in Summer

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 31% of the time across summer.

0%25%50%75%100%DecJanFeb

Chance of precipitation in Summer

Any precipitation

Viamão gets around 397 mm of rain over 41 wet days across summer. The line is the day-by-day chance of measurable precipitation.

0%20%40%60%DecJanFeb

Humidity in Summer

DryComfortableHumidMuggyOppressiveMiserable

Most of summer feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.

0%25%50%75%100%DecJanFeb

Wind in Summer

Winds average 11 km/h across summer.

051015DecJanFeb

Sunrise & sunset in Summer

DaylightNight

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.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMDecJanFeb

Solar energy in Summer

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day across summer, about 6.3 kWh/m².

0246DecJanFeb
Planning a trip in summer

Is summer a good time to visit Viamão?

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.

4.9
Sightseeing
4th-best month of the year
6.4
Beach & pool
1st-best month of the year

summer is a reasonable time to visit Viamão for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Viamão in Summer

From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In summer, Viamão sees daytime highs around 29°C and nights near 20°C. Pack light clothes, rain gear and sun protection. About 41 days see rain.

light clothesrain gearsun protection

Sea temperature near Viamão 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 34 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.

15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swimcomfortable to swim
Sea temperature (°C)Comfort
Jan26Warm
Feb26Warm
Mar25Warm
Apr23Refreshing
May19Cool
Jun17Cool
Jul15Cool
Aug16Cool
Sep17Cool
Oct20Cool
Nov22Refreshing
Dec24Warm

UV index in Viamão in Summer

LowModerateHighVery highExtreme

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 Viamão 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highModerateVery highExtremeJan 15UV 13Jun 19UV 3
UV index (midday)Level
Jan13Extreme
Feb12Extreme
Mar10Very high
Apr7Very high
May4Moderate
Jun3Moderate
Jul4Moderate
Aug5Moderate
Sep8Very high
Oct8Very high
Nov11Extreme
Dec12Extreme

Air quality in Viamão in Summer

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where summer falls, not just the annual average.

Air quality in Viamão 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).

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateAug 1327 µg/m³Dec 2213 µg/m³
PM2.5 (µg/m³)Level
Jan13Moderate
Feb13Moderate
Mar15Moderate
Apr18Moderate
May21Moderate
Jun23Moderate
Jul25Moderate
Aug27Moderate
Sep23Moderate
Oct16Moderate
Nov15Moderate
Dec13Moderate
Location & terrain

Where is Viamão?

Viamão sits at 30.1°S, 51.0°W, 108 m above sea level, in Brazil. The nearest listed city is Alvorada, 10 km away.

Topography around Viamão

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Viamão.

Within 3 km, the terrain around Viamão has only modest variations in elevation — a maximum elevation change of 101 m around an average of 70 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 310 m; within 80 km, large variations in elevation — a maximum elevation change of 941 m.

The land around Viamão is covered by trees (60%) and artificial surfaces (22%) within 3 km, trees (47%) and grassland (25%) within 16 km, and trees (38%), grassland (21%) and water (20%) within 80 km.

3 km
101 m
16 km
310 m
80 km
941 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
Summer weather nearby: Alvorada 10 km · Gravataí 16 km · Cachoeirinha 16 km · Porto Alegre 21 km · Canoas 24 km · Esteio 29 km · Guaíba 29 km · Sapucaia do Sul 32 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
Roman Catholic 57%Evangelical 27%none 9%other 4%

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 Viamão (-30.0811°, -51.0233°, elevation 108 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.