São Sebastião do Caí in Fall
In fall (March, April and May), São Sebastião do Caí sees average daytime highs around 24°C and overnight lows near 15°C, with 431 mm of rain over about 37 wet days across the season. It is the 2nd-warmest season and the driest season of the year.
Over the season highs ease from about 28°C in early March to 19°C by late May. The sky is clear or mostly clear about 33% of the time across fall, and the air most often feels humid.
Fall is São Sebastião do Caí's best season of the year to visit on our travel score. For the whole year in context, see São Sebastião do Caí's year-round climate.
- Avg daytime high
- 24°C
- 2nd-warmest season
- Avg overnight low
- 15°C
- Rainfall
- 431 mm
- 37 wet days
- Avg wind
- 8 km/h
- Travel score
- 6.3
- best season of the year
- Months
- Mar · Apr · May
Temperature in São Sebastião do Caí in Fall
Over the season highs ease from about 28°C in early March to 19°C by late May.
A typical fall day in São Sebastião do Caí reaches about 24°C and drops to 15°C overnight. The warmest of the three months is March, the coolest May.
São Sebastião do Caí weather by month
How the three fall months (March, April and May) 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 | 29° / 19° | 209 | 17.6 | 13.7 | 4.7 |
| Feb | 28° / 19° | 180 | 16.6 | 13.1 | 4.8 |
| Mar | 27° / 18° | 154 | 15.2 | 12.2 | 5.8 |
| Apr | 24° / 15° | 142 | 11.2 | 11.3 | 6.6 |
| May | 21° / 12° | 136 | 10.4 | 10.5 | 6.4 |
| Jun | 19° / 10° | 144 | 10.3 | 10.1 | 6.0 |
| Jul | 19° / 9° | 180 | 10.8 | 10.3 | 6.0 |
| Aug | 21° / 11° | 145 | 10.7 | 10.9 | 6.4 |
| Sep | 22° / 12° | 178 | 12.5 | 11.8 | 6.1 |
| Oct | 24° / 14° | 216 | 14.8 | 12.7 | 6.0 |
| Nov | 26° / 16° | 164 | 12.8 | 13.5 | 6.2 |
| Dec | 28° / 18° | 182 | 15.1 | 13.9 | 5.4 |
Cloud cover in Fall
The sky is clear or mostly clear about 33% of the time across fall.
Chance of precipitation in Fall
São Sebastião do Caí gets around 431 mm of rain over 37 wet days across fall. The line is the day-by-day chance of measurable precipitation.
Humidity in Fall
Most of fall feels humid — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Fall
Winds average 8 km/h across fall.
Sunrise & sunset in Fall
Daylight runs from about 12 h 42 min in early March to 10 h 18 min by late May. The lit band spans sunrise to sunset each day.
Solar energy in Fall
Average shortwave solar energy reaching the ground each day across fall, about 3.8 kWh/m².
Is fall a good time to visit São Sebastião do Caí?
Our two travel scores rate fall for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
fall is a reasonable time to visit São Sebastião do Caí for sightseeing.
What to pack for São Sebastião do Caí in Fall
From fall's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In fall, São Sebastião do Caí sees daytime highs around 24°C and nights near 15°C. Pack light clothes and rain gear. Worth having: sun protection. About 37 days see rain.
UV index in São Sebastião do Caí in Fall
Clear-sky midday UV across fall averages around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in São Sebastião do Caí peaks around January 16 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 20 at about 4 (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 | 8 | 5 | 4 | 4 | 5 | 8 | 8 | 12 | 13 |
| Level | Extreme | Extreme | Very high | Very high | Moderate | Moderate | Moderate | High | Very high | Very high | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 13 | Extreme |
| Feb | 12 | Extreme |
| Mar | 10 | Very high |
| Apr | 8 | Very high |
| May | 5 | Moderate |
| Jun | 4 | Moderate |
| Jul | 4 | Moderate |
| Aug | 5 | High |
| Sep | 8 | Very high |
| Oct | 8 | Very high |
| Nov | 12 | Extreme |
| Dec | 13 | Extreme |
Air quality in São Sebastião do Caí in Fall
Average fine-particle pollution (PM2.5) through the year — so you can see where fall falls, not just the annual average.
Air quality in São Sebastião do Caí is worst in September — around 17 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (December, 10 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) | 10 | 10 | 10 | 12 | 12 | 11 | 13 | 16 | 17 | 12 | 11 | 10 |
| Level | Good | Good | Good | Good | Good | Good | Moderate | Moderate | Moderate | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 10 | Good |
| Feb | 10 | Good |
| Mar | 10 | Good |
| Apr | 12 | Good |
| May | 12 | Good |
| Jun | 11 | Good |
| Jul | 13 | Moderate |
| Aug | 16 | Moderate |
| Sep | 17 | Moderate |
| Oct | 12 | Good |
| Nov | 11 | Good |
| Dec | 10 | Good |
Where is São Sebastião do Caí?
São Sebastião do Caí sits at 29.6°S, 51.4°W, 16 m above sea level, in Brazil. The nearest listed city is Montenegro, 14 km away.
Topography around São Sebastião do Caí
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of São Sebastião do Caí.
Within 3 km, the terrain around São Sebastião do Caí has only modest variations in elevation — a maximum elevation change of 107 m around an average of 32 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 512 m; within 80 km, large variations in elevation — a maximum elevation change of 988 m.
The land around São Sebastião do Caí is covered by trees (69%) within 3 km, trees (73%) within 16 km, and trees (62%) 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 São Sebastião do Caí (-29.5867°, -51.3756°, elevation 16 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.