São Mateus do Maranhão weather in May

In May, São Mateus do Maranhão sees average daytime highs of 31°C and overnight lows near 24°C, with 134 mm of rain across 19.2 wet days and about 11.8 hours of daylight. It is the 9th-warmest and 5th-wettest month of the year here.

Day-to-day highs hold fairly steady near 31°C through the month. The sky is clear or mostly clear about 17% of the time in May, and the air most often feels miserable.

Daylight stretches from about 11 h 54 min at the start of May to 11 h 48 min by month's end. Set against the rest of the year, May is São Mateus do Maranhão's 7th-clearest and 9th-windiest month. For the whole year in context, see São Mateus do Maranhão's year-round climate.

Daytime high
31°
9th warmest
Overnight low
24°
7th coldest
Rainfall
134 mm
19.2 wet days
Daylight
11 h 48 min
6:00 AM – 5:49 PM
Cloud cover
67%
7th clearest
Wind
6 km/h
9th windiest
Solar energy
4.65 kWh/m²
Travel score
3.4
out of 10

São Mateus do Maranhão is settlement in Brazil.

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 31°C through the month.

A typical May day in São Mateus do Maranhão reaches about 31°C in the afternoon and slips back to 24°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 30°C and 33°C. Set against its neighbours, May runs on par with April and on par with June.

20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13124
23124
33124
43124
53124
63124
73124
83124
93124
103124
113124
123124
133124
143124
153124
163224
173224
183224
193224
203224
213224
223224
233224
243224
253224
263224
273224
283224
293224
303224
313224

How May really feels in São Mateus do Maranhão

Once humidity and wind are folded in, May averages 31 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
31
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in May is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

São Mateus do Maranhão weather by month

How May compares with the rest of the year at a glance. May is the 9th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan32° / 24°24224.312.22.6
Feb31° / 24°2632512.12.5
Mar31° / 24°31228.6122.5
Apr31° / 24°27727.111.92.6
May31° / 24°13419.211.83.4
Jun32° / 23°377.611.84.4
Jul33° / 23°183.611.84.3
Aug34° / 24°51.211.93.7
Sep35° / 25°61.1123.0
Oct36° / 25°133.112.12.6
Nov35° / 25°446.812.22.6
Dec34° / 25°11314.312.22.6

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 17% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 24% of May, with mostly cloudy or overcast conditions the remaining 58%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12476
22476
32575
42674
52872
62872
73070
83070
93268
103466
113565
123763
133862
144060
154258
164258
174456
184654
194753
204753
214951
225050
235248
245248
255446
265545
275644
285743
295743
305842
315941

Chance of precipitation in May

Any precipitation

São Mateus do Maranhão gets around 134 mm of rain over 19.2 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 62% and peaks near 78% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%80%151015202531
Rain chance (%)
178
277
376
474
572
671
769
868
966
1065
1164
1263
1362
1462
1561
1661
1760
1860
1959
2059
2158
2258
2357
2456
2555
2654
2752
2851
2949
3047
3145

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the miserable band about 63% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Muggy (%)Oppressive (%)Miserable (%)
102872
202872
302872
402872
502872
602872
702872
802872
902872
1002971
1102971
1203070
1303169
1403268
1503367
1603565
1703664
1803862
1903961
2004060
2104159
2204357
2304456
2404555
2504753
2604852
2705050
2805149
2915247
3015445
3115643

Wind in May

Winds average 6 km/h in May.

Across May, daily wind ranges from about 6 km/h on the calmest days to 6 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm
316calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 11 h 54 min at the start of May to 11 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 6 minutes over May. Sunrise moves from 5:59 AM to 6:02 AM, and sunset from 5:51 PM to 5:49 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.95:595:51
211.95:595:51
311.95:595:50
411.95:595:50
511.85:595:50
611.85:595:50
711.85:595:50
811.85:595:50
911.85:595:49
1011.85:595:49
1111.85:595:49
1211.85:595:49
1311.85:595:49
1411.85:595:49
1511.86:005:49
1611.86:005:49
1711.86:005:49
1811.86:005:49
1911.86:005:49
2011.86:005:48
2111.86:005:48
2211.86:005:48
2311.86:005:48
2411.86:015:48
2511.86:015:48
2611.86:015:49
2711.86:015:49
2811.86:015:49
2911.86:015:49
3011.86:025:49
3111.86:025:49

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 4.65 kWh/m².

For context, solar energy here swings from a low near 4.39 kWh/m² to a high of 6.36 kWh/m² in October across the year — May's 4.65 kWh/m² sits near the bottom.

024151015202531
Solar energy (kWh/m²)Level
14.4Bright
24.4Bright
34.4Bright
44.5Bright
54.5Bright
64.5Bright
74.5Bright
84.5Bright
94.6Bright
104.6Bright
114.6Bright
124.6Bright
134.7Bright
144.7Bright
154.7Bright
164.7Bright
174.7Bright
184.7Bright
194.7Bright
204.7Bright
214.7Bright
224.8Bright
234.8Bright
244.8Bright
254.8Bright
264.8Bright
274.8Bright
284.8Bright
294.8Bright
304.8Bright
314.8Bright
Planning a trip in May

Hazard calendar for São Mateus do Maranhão

In seasonPeak

None of São Mateus do Maranhão'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 Mateus do Maranhão's monsoon runs January–April, 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 Mateus do Maranhão?

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

3.4
Sightseeing
4th-best month of the year
5.2
Beach & pool
8th-best month of the year

May is a weaker month for outdoor sightseeing in São Mateus do Maranhão.

What to pack for São Mateus do Maranhão in May

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

In May, São Mateus do Maranhão sees daytime highs around 31°C and nights near 24°C. Pack light clothes and rain gear. Worth having: sun protection. About 19 days see rain.

light clothesrain gearsun protection

UV index in São Mateus do Maranhão in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 11 (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 Mateus do Maranhão peaks around March 16 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 24 at about 10 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeMar 16UV 15Jul 24UV 10
UV index (midday)Level
Jan13Extreme
Feb14Extreme
Mar15Extreme
Apr14Extreme
May11Extreme
Jun10Extreme
Jul10Very high
Aug10Very high
Sep12Extreme
Oct12Extreme
Nov11Extreme
Dec11Extreme

Air quality in São Mateus do Maranhão 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 Mateus do Maranhão is worst in October — around 25 µg/m³ PM2.5 (moderate), about 3.0× the cleanest month (June, 8 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateOct 2125 µg/m³Jun 199 µg/m³
PM2.5 (µg/m³)Level
Jan14Moderate
Feb16Moderate
Mar15Moderate
Apr13Moderate
May10Good
Jun8Good
Jul9Good
Aug12Good
Sep16Moderate
Oct25Moderate
Nov23Moderate
Dec17Moderate
Location & terrain

Where is São Mateus do Maranhão?

São Mateus do Maranhão sits at 4.0°S, 44.5°W, 47 m above sea level, in Brazil. The nearest listed city is Alto Alegre do Maranhão, 19 km away.

Topography around São Mateus do Maranhão

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

Within 3 km, the terrain around São Mateus do Maranhão has only modest variations in elevation — a maximum elevation change of 28 m around an average of 42 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 76 m; within 80 km, only modest variations in elevation — a maximum elevation change of 174 m.

The land around São Mateus do Maranhão is covered by grassland (44%) and trees (29%) within 3 km, grassland (50%) and trees (31%) within 16 km, and trees (47%) and grassland (46%) within 80 km.

3 km
28 m
16 km
76 m
80 km
174 m
treesshrubsgrasslandcroplandartificial surfaceswaterwetland
May weather nearby: Alto Alegre do Maranhão 19 km · Bacabal 40 km · Coroatá 40 km · Peritoró 41 km · São Luís Gonzaga do Maranhão 43 km · Pirapemas 45 km · Matões do Norte 46 km · Cantanhede 47 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 Mateus do Maranhão (-4.0417°, -44.475°, elevation 47 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).