Riachão weather in May

In May, Riachão sees average daytime highs of 31°C and overnight lows near 22°C, with 56 mm of rain across 8.6 wet days and about 11.7 hours of daylight. It is the 6th-warmest and 8th-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 31% of the time in May, and the air most often feels muggy.

Daylight stretches from about 11 h 42 min at the start of May to 11 h 36 min by month's end. Set against the rest of the year, May is Riachão's 6th-clearest and 5th-windiest month. For the whole year in context, see Riachão's year-round climate.

Daytime high
31°
6th warmest
Overnight low
22°
8th coldest
Rainfall
56 mm
8.6 wet days
Daylight
11 h 42 min
6:13 AM – 5:53 PM
Cloud cover
58%
6th clearest
Wind
8 km/h
5th windiest
Solar energy
5.11 kWh/m²
Travel score
4.4
out of 10

Riachão 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 Riachão reaches about 31°C in the afternoon and slips back to 22°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 29°C and 34°C. Set against its neighbours, May runs about 1°C warmer than April and about 1°C cooler than June.

20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13122
23122
33122
43122
53122
63122
73122
83122
93122
103122
113122
123122
133122
143122
153222
163222
173222
183222
193222
203222
213222
223222
233222
243222
253222
263222
273222
283222
293222
303222
313222

How May really feels in Riachão

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.

Riachão weather by month

How May compares with the rest of the year at a glance. May is the 6th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 22°30827.212.43.0
Feb30° / 22°26824.512.23.0
Mar30° / 22°27226.7123.0
Apr31° / 22°14918.411.83.7
May31° / 22°568.611.74.4
Jun32° / 22°40.611.65.0
Jul33° / 22°10.211.64.8
Aug34° / 22°20.411.84.0
Sep35° / 23°162.7123.2
Oct33° / 23°869.912.23.4
Nov31° / 22°18518.312.33.5
Dec30° / 22°22723.512.43.3

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 31% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 21% of May, with mostly cloudy or overcast conditions the remaining 48%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13961
23961
34159
44159
54159
64357
74357
84555
94753
104852
114951
124951
135050
145149
155248
165248
175347
185347
195446
205545
215644
225743
235743
245941
256040
266139
276238
286436
296634
306733
316832

Chance of precipitation in May

Any precipitation

Riachão gets around 56 mm of rain over 8.6 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 27% and peaks near 44% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202531
Rain chance (%)
144
243
342
441
540
638
737
836
934
1033
1131
1230
1329
1428
1527
1626
1725
1824
1924
2023
2122
2221
2320
2419
2518
2617
2716
2815
2914
3012
3111

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 90% of them.

0%25%50%75%100%151015202531
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1013069
2013168
3013366
4023464
5023662
6023860
7024058
8034156
9034354
10034552
11044749
12044947
13045145
14055144
15055342
16065440
17075439
18085438
19095536
200105535
210115633
220125632
230145630
240165529
251185427
261205425
271225324
281245322
291275220
301295119
311325017

Wind in May

Winds average 8 km/h in May.

Across May, daily wind ranges from about 7 km/h on the calmest days to 9 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
17calm
27calm
37calm
47calm
57calm
68calm
78calm
88calm
98calm
108calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
229calm
239calm
249calm
259calm
269calm
279calm
289calm
299calm
309calm
319calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 11 h 42 min at the start of May to 11 h 36 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 6:11 AM to 6:16 AM, and sunset from 5:56 PM to 5:52 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.76:115:56
211.76:115:56
311.76:115:55
411.76:115:55
511.76:125:55
611.76:125:55
711.76:125:54
811.76:125:54
911.76:125:54
1011.76:125:54
1111.76:125:53
1211.76:125:53
1311.76:125:53
1411.76:125:53
1511.76:135:53
1611.76:135:53
1711.76:135:53
1811.76:135:52
1911.76:135:52
2011.66:135:52
2111.66:145:52
2211.66:145:52
2311.66:145:52
2411.66:145:52
2511.66:145:52
2611.66:155:52
2711.66:155:52
2811.66:155:52
2911.66:155:52
3011.66:155:52
3111.66:165:52

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.11 kWh/m².

For context, solar energy here swings from a low near 4.88 kWh/m² to a high of 6.55 kWh/m² in September across the year — May's 5.11 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
35.0Bright
45.0Bright
55.0Bright
65.1Bright
75.1Bright
85.1Bright
95.1Bright
105.1Bright
115.1Bright
125.1Bright
135.1Bright
145.1Bright
155.1Bright
165.1Bright
175.1Bright
185.1Bright
195.1Bright
205.1Bright
215.1Bright
225.1Bright
235.1Bright
245.1Bright
255.2Bright
265.2Bright
275.2Bright
285.2Bright
295.2Bright
305.2Bright
315.2Bright
Planning a trip in May

Hazard calendar for Riachão

In seasonPeak

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

Riachão's monsoon runs November–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 Riachão?

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

4.4
Sightseeing
3rd-best month of the year
6.8
Beach & pool
5th-best month of the year

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

What to pack for Riachão in May

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

In May, Riachão sees daytime highs around 31°C and nights near 22°C. Pack light clothes. Worth having: rain gear and sun protection. About 9 days see rain.

light clothesrain gearsun protection

UV index in Riachão 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 Riachão peaks around February 21 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 22 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 highExtremeFeb 21UV 15Jun 22UV 10
UV index (midday)Level
Jan14Extreme
Feb15Extreme
Mar15Extreme
Apr14Extreme
May11Extreme
Jun10Very high
Jul10Very high
Aug11Extreme
Sep12Extreme
Oct12Extreme
Nov12Extreme
Dec11Extreme

Air quality in Riachão 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 Riachão is worst in September — around 30 µg/m³ PM2.5 (moderate), about 5.1× the cleanest month (June, 6 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateSep 2029 µg/m³Jun 186 µg/m³
PM2.5 (µg/m³)Level
Jan12Good
Feb11Good
Mar11Good
Apr11Good
May7Good
Jun6Good
Jul7Good
Aug15Moderate
Sep30Moderate
Oct26Moderate
Nov17Moderate
Dec14Moderate
Location & terrain

Where is Riachão?

Riachão sits at 7.4°S, 46.6°W, 385 m above sea level, in Brazil. The nearest listed city is Balsas, 67 km away.

Topography around Riachão

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

Within 3 km, the terrain around Riachão has only modest variations in elevation — a maximum elevation change of 80 m around an average of 378 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 374 m; within 80 km, significant variations in elevation — a maximum elevation change of 475 m.

The land around Riachão is covered by grassland (47%), trees (25%) and shrubs (20%) within 3 km, grassland (45%), trees (33%) and shrubs (21%) within 16 km, and trees (36%), grassland (36%) and shrubs (20%) within 80 km.

3 km
80 m
16 km
374 m
80 km
475 m
treesshrubsgrasslandcroplandartificial surfaces
May weather nearby: Balsas 67 km · Carolina 93 km · Formosa da Serra Negra 112 km · Estreito 128 km · São Raimundo das Mangabeiras 131 km · Porto Franco 143 km · Tocantinópolis 145 km · Sítio Novo 165 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 Riachão (-7.3619°, -46.6172°, elevation 385 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).