São Sebastião do Caí weather in March

In March, São Sebastião do Caí sees average daytime highs of 27°C and overnight lows near 18°C, with 154 mm of rain across 15.2 wet days and about 12.2 hours of daylight. It is the 4th-warmest and 8th-wettest month of the year here.

Highs ease over the month, from about 28°C in the first days to 26°C by the end. The sky is clear or mostly clear about 32% of the time in March, and the air most often feels muggy.

Daylight stretches from about 12 h 42 min at the start of March to 11 h 48 min by month's end. Set against the rest of the year, March is São Sebastião do Caí's 3rd-clearest and 11th-windiest month. For the whole year in context, see São Sebastião do Caí's year-round climate.

Daytime high
27°
4th warmest
Overnight low
18°
9th coldest
Rainfall
154 mm
15.2 wet days
Daylight
12 h 12 min
7:29 AM – 7:42 PM
Cloud cover
57%
3rd clearest
Wind
8 km/h
11th windiest
Solar energy
4.85 kWh/m²
Travel score
5.8
out of 10

Temperature in March

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 28°C in the first days to 26°C by the end.

A typical March day in São Sebastião do Caí reaches about 27°C in the afternoon and slips back to 18°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 23°C and 31°C. Set against its neighbours, March runs about 1°C cooler than February and about 3°C warmer than April.

10°15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
12818
22818
32818
42818
52818
62818
72818
82818
92818
102818
112818
122818
132718
142718
152718
162718
172718
182717
192717
202717
212717
222717
232717
242617
252617
262617
272617
282617
292617
302617
312616

São Sebastião do Caí weather by month

How March compares with the rest of the year at a glance. March is the 4th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 19°20917.613.74.7
Feb28° / 19°18016.613.14.8
Mar27° / 18°15415.212.25.8
Apr24° / 15°14211.211.36.6
May21° / 12°13610.410.56.4
Jun19° / 10°14410.310.16.0
Jul19° / 18010.810.36.0
Aug21° / 11°14510.710.96.4
Sep22° / 12°17812.511.86.1
Oct24° / 14°21614.812.76.0
Nov26° / 16°16412.813.56.2
Dec28° / 18°18215.113.95.4

Cloud cover in March

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 32% of the time in March.

Beyond those clear spells, partly cloudy skies cover about 19% of March, with mostly cloudy or overcast conditions the remaining 49%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14852
24951
35050
45050
55050
65050
75050
85050
95149
105149
115149
125149
135248
145149
155248
165248
175149
185248
195248
205248
215149
225248
235149
245149
255149
265050
275050
285149
295149
305149
315149

Chance of precipitation in March

Any precipitation

São Sebastião do Caí gets around 154 mm of rain over 15.2 wet days in March. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 49% and peaks near 54% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
154
254
354
453
553
653
752
852
952
1051
1151
1251
1350
1450
1550
1650
1749
1849
1948
2048
2147
2247
2346
2446
2546
2645
2744
2844
2943
3042
3141

Humidity in March

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, March lands in the muggy band about 42% of days. Sticky, muggy-or-worse air turns up on roughly 54% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
118244126
219254125
319254124
419264123
519264222
619274221
719274320
819274319
919284418
10110284418
11110284517
12110284516
13210284515
14211294514
15211294513
16212304412
17312304411
18313314310
1941331439
2041431428
2151532427
2251532417
2351533416
2461633405
2561633405
2661634395
2771734394
2871734384
2971734374
3081834374
3181834364

Wind in March

Winds average 8 km/h in March.

Across March, daily wind ranges from about 8 km/h on the calmest days to 8 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
18calm
28calm
38calm
48calm
58calm
68calm
78calm
88calm
98calm
108calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm
318calm

Sunrise & sunset in March

DaylightNight

Daylight runs from about 12 h 42 min at the start of March to 11 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 54 minutes over March. Sunrise moves from 7:19 AM to 7:38 AM, and sunset from 7:59 PM to 7:23 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.77:197:59
212.67:197:58
312.67:207:57
412.67:217:56
512.67:217:55
612.57:227:53
712.57:237:52
812.57:237:51
912.47:247:50
1012.47:257:49
1112.47:257:48
1212.37:267:47
1312.37:277:45
1412.37:277:44
1512.37:287:43
1612.27:297:42
1712.27:297:41
1812.27:307:39
1912.17:307:38
2012.17:317:37
2112.17:327:36
2212.07:327:34
2312.07:337:33
2412.07:337:32
2511.97:347:31
2611.97:357:30
2711.97:357:28
2811.97:367:27
2911.87:367:26
3011.87:377:25
3111.87:387:23

Solar energy in March

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in March, about 4.85 kWh/m².

For context, solar energy here swings from a low near 2.41 kWh/m² to a high of 6.44 kWh/m² in December across the year — March's 4.85 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.3Bright
25.3Bright
35.2Bright
45.2Bright
55.2Bright
65.2Bright
75.2Bright
85.1Bright
95.1Bright
105.1Bright
115.0Bright
125.0Bright
135.0Bright
145.0Bright
154.9Bright
164.9Bright
174.8Bright
184.8Bright
194.8Bright
204.7Bright
214.7Bright
224.6Bright
234.6Bright
244.5Bright
254.5Bright
264.5Bright
274.5Bright
284.4Bright
294.4Bright
304.3Bright
314.3Bright
Planning a trip in March

Is March a good time to visit São Sebastião do Caí?

Our two travel scores rate March for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

5.8
Sightseeing
9th-best month of the year
5.9
Beach & pool
3rd-best month of the year

March is a reasonable time to visit São Sebastião do Caí for sightseeing.

What to pack for São Sebastião do Caí in March

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

In March, São Sebastião do Caí sees daytime highs around 27°C and nights near 18°C. Pack light clothes and rain gear. Worth having: sun protection. About 15 days see rain.

light clothesrain gearsun protection

UV index in São Sebastião do Caí in March

LowModerateHighVery highExtreme

Clear-sky midday UV in March peaks around 10 (very high — sun protection essential). 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highModerateHighVery highExtremeJan 16UV 13Jun 20UV 4
UV index (midday)Level
Jan13Extreme
Feb12Extreme
Mar10Very high
Apr8Very high
May5Moderate
Jun4Moderate
Jul4Moderate
Aug5High
Sep8Very high
Oct8Very high
Nov12Extreme
Dec13Extreme

Air quality in São Sebastião do Caí in March

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where March 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).

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 1217 µg/m³Dec 1910 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb10Good
Mar10Good
Apr12Good
May12Good
Jun11Good
Jul13Moderate
Aug16Moderate
Sep17Moderate
Oct12Good
Nov11Good
Dec10Good
Location & terrain

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.

3 km
107 m
16 km
512 m
80 km
988 m
treesgrasslandcroplandartificial surfaceswaterwetland
March weather nearby: Montenegro 14 km · Portão 18 km · Estância Velha 21 km · Ivoti 21 km · Novo Hamburgo 26 km · Dois Irmãos 28 km · São Leopoldo 29 km · Nova Santa Rita 31 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 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. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).