São Sebastião weather in May

In May, São Sebastião sees average daytime highs of 27°C and overnight lows near 16°C, with 17 mm of rain across 3.2 wet days and about 11.3 hours of daylight. It is the 10th-warmest and 9th-wettest month of the year here.

Day-to-day highs hold fairly steady near 27°C through the month. The sky is clear or mostly clear about 47% of the time in May, and the air most often feels comfortable.

Daylight stretches from about 11 h 24 min at the start of May to 11 h 06 min by month's end. Set against the rest of the year, May is São Sebastião's 5th-clearest and 6th-windiest month. For the whole year in context, see São Sebastião's year-round climate.

Daytime high
27°
10th warmest
Overnight low
16°
4th coldest
Rainfall
17 mm
3.2 wet days
Daylight
11 h 18 min
7:30 AM – 6:45 PM
Cloud cover
46%
5th clearest
Wind
8 km/h
6th windiest
Solar energy
4.82 kWh/m²
Travel score
7.7
out of 10

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 27°C through the month.

A typical May day in São Sebastião reaches about 27°C in the afternoon and slips back to 16°C overnight — a 11°C spread between the day's warmth and the night's chill. On most days the high lands between 25°C and 29°C. Set against its neighbours, May runs on par with April and on par with June.

10°15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12817
22817
32817
42817
52817
62817
72817
82717
92717
102716
112716
122716
132716
142716
152716
162716
172716
182716
192716
202716
212716
222716
232716
242716
252716
262716
272716
282716
292715
302715
312715

São Sebastião weather by month

How May compares with the rest of the year at a glance. May is the 10th-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan28° / 19°2032112.84.6
Feb28° / 19°16018.212.54.8
Mar28° / 19°18120.112.14.8
Apr28° / 18°7111.311.76.1
May27° / 16°173.211.37.7
Jun27° / 14°40.611.18.4
Jul27° / 14°0011.18.6
Aug29° / 15°51.211.57.5
Sep30° / 18°284.811.95.6
Oct30° / 19°10413.312.44.6
Nov28° / 19°20121.212.74.3
Dec28° / 19°22523.212.94.3

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 47% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 20% of May, with mostly cloudy or overcast conditions the remaining 33%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
17030
26931
37030
47030
56931
66832
76832
86634
96535
106436
116337
126238
136238
146139
156139
166139
176139
186238
196238
206436
216535
226535
236733
246832
256931
267030
277228
287327
297327
307525
317525

Chance of precipitation in May

Any precipitation

São Sebastião gets around 17 mm of rain over 3.2 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 11% and peaks near 15% on the wettest days.

0%10%20%30%151015202531
Rain chance (%)
115
214
313
412
511
611
711
811
911
1011
1111
1211
1311
1412
1512
1612
1712
1812
1912
2011
2111
2211
2311
2410
2510
269
279
288
298
307
317

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the comfortable band about 45% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
14374515
24384414
35404312
45424211
56434110
6744409
7745408
8846397
9847396
10947386
111047385
121047385
131147375
141147374
151247374
161347374
171347363
181446363
191546363
201646363
211645363
221745352
231845342
241946332
252046322
262147311
272147301
282248291
292348281
302448270
312549260

Wind in May

Winds average 8 km/h in May.

Across May, 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.

051015151015202531
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 May

DaylightNight

Daylight runs from about 11 h 24 min at the start of May to 11 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 18 minutes over May. Sunrise moves from 7:25 AM to 7:35 AM, and sunset from 6:51 PM to 6:42 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.47:256:51
211.47:256:51
311.47:266:50
411.47:266:50
511.47:266:49
611.47:276:49
711.47:276:49
811.37:276:48
911.37:276:48
1011.37:286:47
1111.37:286:47
1211.37:286:47
1311.37:296:46
1411.37:296:46
1511.37:296:45
1611.37:306:45
1711.37:306:45
1811.27:306:45
1911.27:306:44
2011.27:316:44
2111.27:316:44
2211.27:316:44
2311.27:326:43
2411.27:326:43
2511.27:326:43
2611.27:336:43
2711.27:336:43
2811.27:346:43
2911.17:346:43
3011.17:346:43
3111.17:356:42

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 4.82 kWh/m².

For context, solar energy here swings from a low near 4.62 kWh/m² to a high of 6.14 kWh/m² in October across the year — May's 4.82 kWh/m² sits near the bottom.

0246151015202531
Solar energy (kWh/m²)Level
15.1Bright
25.1Bright
35.1Bright
45.1Bright
55.0Bright
65.0Bright
75.0Bright
85.0Bright
94.9Bright
104.9Bright
114.9Bright
124.9Bright
134.8Bright
144.8Bright
154.8Bright
164.8Bright
174.7Bright
184.7Bright
194.7Bright
204.7Bright
214.7Bright
224.7Bright
234.7Bright
244.7Bright
254.7Bright
264.7Bright
274.7Bright
284.6Bright
294.6Bright
304.6Bright
314.6Bright
Planning a trip in May

Hazard calendar for São Sebastião

In seasonPeak

None of São Sebastião's seasonal hazards are active in May. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

São Sebastião's monsoon runs October–March, when most of the year's rain falls.

Monsoon
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is May a good time to visit São Sebastião?

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

7.7
Sightseeing
3rd-best month of the year
7.8
Beach & pool
4th-best month of the year

May is one of the better times to visit São Sebastião for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for São Sebastião in May

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

In May, São Sebastião sees daytime highs around 27°C and nights near 16°C. Pack light clothes. Worth having: sun protection. About 3 days see rain.

light clothessun protection

UV index in São Sebastião in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May 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 peaks around February 15 at about 16 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 23 at about 8 (very high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeFeb 15UV 16Jun 23UV 8
UV index (midday)Level
Jan15Extreme
Feb16Extreme
Mar15Extreme
Apr12Extreme
May10Very high
Jun8Very high
Jul8Very high
Aug10Very high
Sep13Extreme
Oct13Extreme
Nov15Extreme
Dec13Extreme

Air quality in São Sebastião in May

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in São Sebastião is worst in September — around 32 µg/m³ PM2.5 (moderate), about 2.8× the cleanest month (January, 11 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

010203040JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateSep 1830 µg/m³Jan 1511 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb13Moderate
Mar15Moderate
Apr14Moderate
May15Moderate
Jun13Moderate
Jul13Moderate
Aug15Moderate
Sep32Moderate
Oct21Moderate
Nov13Moderate
Dec12Moderate
Location & terrain

Where is São Sebastião?

São Sebastião sits at 15.9°S, 47.8°W, 1,048 m above sea level, in Brazil. The nearest listed city is Jardim Botânico, 6.0 km away.

Topography around São Sebastião

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

Within 3 km, the terrain around São Sebastião has only modest variations in elevation — a maximum elevation change of 233 m around an average of 968 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 343 m; within 80 km, large variations in elevation — a maximum elevation change of 779 m.

The land around São Sebastião is covered by grassland (34%), artificial surfaces (31%) and trees (23%) within 3 km, grassland (39%), trees (24%) and shrubs (21%) within 16 km, and grassland (34%), trees (25%) and cropland (22%) within 80 km.

3 km
233 m
16 km
343 m
80 km
779 m
treesshrubsgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Jardim Botânico 6.0 km · Lago Sul 13 km · Paranoá 14 km · Plano Piloto 17 km · Itapoã 17 km · Park Way 18 km · Sudoeste/Octagonal 20 km · Lago Norte 20 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 (-15.9029°, -47.7761°, elevation 1,048 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).