São João de Meriti weather in May

In May, São João de Meriti sees average daytime highs of 26°C and overnight lows near 18°C, with 74 mm of rain across 11.1 wet days and about 10.9 hours of daylight. It is the 9th-warmest and 9th-wettest month of the year here.

Highs ease over the month, from about 27°C in the first days to 26°C by the end. The sky is clear or mostly clear about 36% of the time in May, and the air most often feels muggy.

Daylight stretches from about 11 h 12 min at the start of May to 10 h 42 min by month's end. Set against the rest of the year, May is São João de Meriti's 4th-clearest and 10th-windiest month. For the whole year in context, see São João de Meriti's year-round climate.

Daytime high
26°
9th warmest
Overnight low
18°
5th coldest
Rainfall
74 mm
11.1 wet days
Daylight
10 h 54 min
7:23 AM – 6:17 PM
Cloud cover
53%
4th clearest
Wind
5 km/h
10th windiest
Solar energy
3.53 kWh/m²
Travel score
6.6
out of 10

São João de Meriti is human settlement in Brazil.

Air quality
Moderate
PM2.5 12 µg/m³ · 2015

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 27°C in the first days to 26°C by the end.

A typical May day in São João de Meriti reaches about 26°C in the afternoon and slips back to 18°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 23°C and 30°C. Set against its neighbours, May runs about 2°C cooler than April and on par with June.

10°15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
12819
22719
32719
42719
52719
62719
72719
82719
92719
102719
112718
122718
132618
142618
152618
162618
172618
182618
192618
202618
212618
222618
232618
242618
252618
262618
272618
282618
292617
302617
312617

How May really feels in São João de Meriti

Once humidity and wind are folded in, May averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

May sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

São João de Meriti weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan31° / 23°26621.313.23.2
Feb32° / 23°19717.812.83.3
Mar30° / 22°21621.112.23.7
Apr29° / 21°10613.511.55.2
May26° / 18°7411.110.96.6
Jun26° / 17°477.110.67.3
Jul26° / 16°477.210.77.4
Aug26° / 17°447.511.27.2
Sep27° / 18°8711.111.96.3
Oct28° / 20°12014.412.55.3
Nov28° / 21°2131913.14.4
Dec30° / 22°23721.213.43.6

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 36% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 22% of May, with mostly cloudy or overcast conditions the remaining 42%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16238
26238
36238
46238
56238
66139
76040
86040
95941
105842
115842
125644
135644
145644
155644
165545
175545
185644
195644
205644
215743
225743
235743
245842
255842
265941
275941
285941
295941
305941
316040

Chance of precipitation in May

Any precipitation

São João de Meriti gets around 74 mm of rain over 11.1 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 36% and peaks near 38% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202531
Rain chance (%)
138
238
338
438
538
638
738
838
938
1038
1138
1238
1338
1437
1537
1637
1736
1836
1935
2035
2134
2234
2334
2433
2533
2633
2733
2832
2932
3032
3131

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the muggy band about 48% 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 (%)
103245320
204255318
304275316
405285215
505295214
605305213
706315112
806325111
906335110
100634519
110635518
120736507
130737506
140738506
150738495
160739494
170840484
180841483
190841473
200842473
210942463
220942462
2311043452
2411043442
2511144432
2611244422
2711244412
2811344402
2911444392
3011444392
3111544382

Wind in May

Winds average 5 km/h in May.

Across May, daily wind ranges from about 5 km/h on the calmest days to 5 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm
315calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 11 h 12 min at the start of May to 10 h 42 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 30 minutes over May. Sunrise moves from 7:16 AM to 7:29 AM, and sunset from 6:26 PM to 6:12 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.27:166:26
211.17:166:25
311.17:176:24
411.17:176:24
511.17:176:23
611.17:186:22
711.17:186:22
811.07:196:21
911.07:196:21
1011.07:206:20
1111.07:206:19
1211.07:216:19
1311.07:216:18
1410.97:226:18
1510.97:226:17
1610.97:236:17
1710.97:236:17
1810.97:236:16
1910.97:246:16
2010.87:246:15
2110.87:256:15
2210.87:256:15
2310.87:266:14
2410.87:266:14
2510.87:276:14
2610.87:276:13
2710.87:286:13
2810.77:286:13
2910.77:296:13
3010.77:296:13
3110.77:296:12

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 3.53 kWh/m².

For context, solar energy here swings from a low near 3.33 kWh/m² to a high of 5.93 kWh/m² in February across the year — May's 3.53 kWh/m² sits near the bottom.

01234151015202531
Solar energy (kWh/m²)Level
13.9Moderate
23.9Moderate
33.9Moderate
43.9Moderate
53.8Moderate
63.8Moderate
73.8Moderate
83.7Moderate
93.7Moderate
103.7Moderate
113.6Moderate
123.6Moderate
133.6Moderate
143.5Moderate
153.5Moderate
163.5Moderate
173.5Moderate
183.4Moderate
193.4Moderate
203.4Moderate
213.4Moderate
223.4Moderate
233.3Moderate
243.3Moderate
253.3Moderate
263.3Moderate
273.3Moderate
283.3Moderate
293.3Moderate
303.3Moderate
313.3Moderate
Planning a trip in May

Hazard calendar for São João de Meriti

In seasonPeak

None of São João de Meriti'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 João de Meriti's rainy season runs October–March, when most of the year's rain falls.

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

Is May a good time to visit São João de Meriti?

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

6.6
Sightseeing
4th-best month of the year
6.4
Beach & pool
5th-best month of the year

May is a reasonable time to visit São João de Meriti for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for São João de Meriti in May

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

In May, São João de Meriti sees daytime highs around 26°C and nights near 18°C. Worth packing: light clothes and rain gear. About 11 days see rain.

light clothesrain gear

Sea temperature near São João de Meriti in May

The nearest coast averages about 24°C in May — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 36 km away) is warmest in March at about 26°C and coldest in August near 21°C.

The water stays above 20°C all year — warm enough for a swim any month.

20°22°24°26°JanFebMarAprMayJunJulAugSepOctNovDeccoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan25Warm
Feb25Warm
Mar26Warm
Apr25Warm
May24Refreshing
Jun23Refreshing
Jul22Refreshing
Aug21Refreshing
Sep21Refreshing
Oct22Refreshing
Nov22Refreshing
Dec24Warm

UV index in São João de Meriti in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 6 — 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 João de Meriti peaks around January 13 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 13 at about 5 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighExtremeJan 13UV 14Jul 13UV 5
UV index (midday)Level
Jan14Extreme
Feb13Extreme
Mar12Extreme
Apr9Very high
May6High
Jun6High
Jul5Moderate
Aug8Very high
Sep6High
Oct11Extreme
Nov13Extreme
Dec14Extreme

Air quality in São João de Meriti 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 João de Meriti is worst in July — around 17 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (December, 8 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to São João de Meriti's WHO annual average of 12 µg/m³.

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1217 µg/m³Dec 238 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb8Good
Mar9Good
Apr11Good
May14Moderate
Jun16Moderate
Jul17Moderate
Aug14Moderate
Sep17Moderate
Oct11Good
Nov9Good
Dec8Good
Location & terrain

Where is São João de Meriti?

São João de Meriti sits at 22.8°S, 43.4°W, 14 m above sea level, in Brazil. The nearest listed city is Nilópolis, 4.0 km away.

Topography around São João de Meriti

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

Within 3 km, the terrain around São João de Meriti has only modest variations in elevation — a maximum elevation change of 154 m around an average of 27 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 956 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,224 m.

The land around São João de Meriti is covered by artificial surfaces (88%) within 3 km, artificial surfaces (52%) and trees (28%) within 16 km, and trees (37%), water (31%) and grassland (24%) within 80 km.

3 km
154 m
16 km
956 m
80 km
2,224 m
treesgrasslandartificial surfacesbare terrainwaterwetlandmangroves
May weather nearby: Nilópolis 4.0 km · Belford Roxo 5.0 km · Duque de Caxias 7.0 km · Nova Iguaçu 9.0 km · Queimados 21 km · Estácio 21 km · Barra da Tijuca 22 km · Rio de Janeiro 23 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 João de Meriti (-22.8039°, -43.3722°, elevation 14 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).