Castro weather in May

In May, Castro sees average daytime highs of 20°C and overnight lows near 12°C, with 89 mm of rain across 8.9 wet days and about 10.8 hours of daylight. It is the 10th-warmest and 9th-wettest month of the year here.

Highs ease over the month, from about 22°C in the first days to 19°C by the end. The sky is clear or mostly clear about 30% of the time in May, and the air most often feels dry.

Daylight stretches from about 11 h 06 min at the start of May to 10 h 36 min by month's end. Set against the rest of the year, May is Castro's 5th-clearest and 9th-windiest month. For the whole year in context, see Castro's year-round climate.

Daytime high
20°
10th warmest
Overnight low
12°
4th coldest
Rainfall
89 mm
8.9 wet days
Daylight
10 h 48 min
7:52 AM – 6:40 PM
Cloud cover
59%
5th clearest
Wind
10 km/h
9th windiest
Solar energy
3.36 kWh/m²
Travel score
6.5
out of 10

Castro is human 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

Highs ease over the month, from about 22°C in the first days to 19°C by the end.

A typical May day in Castro reaches about 20°C in the afternoon and slips back to 12°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 17°C and 24°C. Set against its neighbours, May runs about 3°C cooler than April and about 1°C warmer than June.

10°15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12213
22213
32213
42213
52113
62112
72112
82112
92112
102112
112112
122112
132012
142012
152012
162012
172012
182012
192011
202011
212011
222011
232011
241911
251911
261911
271911
281911
291911
301911
311911

Castro 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
Jan26° / 17°23523.813.44.5
Feb26° / 17°1782112.94.6
Mar25° / 17°1321812.25.5
Apr23° / 15°709.611.46.9
May20° / 12°898.910.86.5
Jun19° / 11°938.410.56.5
Jul19° / 10°79710.66.8
Aug21° / 11°727.311.17.2
Sep22° / 12°12710.411.86.6
Oct23° / 14°13815.112.65.9
Nov24° / 15°13316.113.25.8
Dec26° / 17°17320.313.55.1

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 30% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 16% of May, with mostly cloudy or overcast conditions the remaining 54%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15149
25149
35149
45050
55050
64852
74852
84753
94654
104555
114456
124456
134357
144357
154357
164357
174258
184258
194357
204456
214456
224456
234555
244555
254555
264654
274753
284753
294654
304753
314951

Chance of precipitation in May

Any precipitation

Castro gets around 89 mm of rain over 8.9 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 29% and peaks near 34% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%151015202531
Rain chance (%)
125
225
325
424
524
625
725
825
925
1025
1125
1226
1326
1427
1527
1628
1729
1829
1930
2030
2131
2231
2332
2432
2533
2633
2733
2834
2934
3034
3133

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the dry band about 54% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
13844181
23944161
34144150
44244130
54344120
64544120
74644110
84743100
94843100
10494290
11504280
12514180
13514180
14534070
15543970
16543970
17553870
18563770
19583570
20593470
21603370
22613270
23613180
24623080
25632980
26642880
27652870
28652870
29662770
30662770
31662770

Wind in May

Winds average 10 km/h in May.

Across May, daily wind ranges from about 10 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
110calm
210calm
310calm
410calm
510calm
610calm
710calm
810calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1510calm
1610calm
1710calm
1811calm
1911calm
2011calm
2111calm
2211calm
2311calm
2411calm
2511calm
2611calm
2711calm
2811calm
2911calm
3011calm
3111calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 11 h 06 min at the start of May to 10 h 36 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 7:45 AM to 8:00 AM, and sunset from 6:50 PM to 6:35 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.17:456:50
211.17:456:49
311.07:466:48
411.07:466:48
511.07:476:47
611.07:476:46
711.07:486:46
810.97:486:45
910.97:496:44
1010.97:496:44
1110.97:506:43
1210.97:506:42
1310.97:516:42
1410.87:516:41
1510.87:526:41
1610.87:526:40
1710.87:536:40
1810.87:536:39
1910.87:546:39
2010.77:546:38
2110.77:556:38
2210.77:556:38
2310.77:566:37
2410.77:566:37
2510.77:576:37
2610.67:576:36
2710.67:586:36
2810.67:586:36
2910.67:596:35
3010.67:596:35
3110.68:006:35

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 3.36 kWh/m².

For context, solar energy here swings from a low near 3.05 kWh/m² to a high of 5.87 kWh/m² in December across the year — May's 3.36 kWh/m² sits near the bottom.

01234151015202531
Solar energy (kWh/m²)Level
13.9Moderate
23.8Moderate
33.8Moderate
43.8Moderate
53.7Moderate
63.7Moderate
73.7Moderate
83.6Moderate
93.6Moderate
103.5Moderate
113.5Moderate
123.5Moderate
133.4Moderate
143.4Moderate
153.4Moderate
163.3Moderate
173.3Moderate
183.3Moderate
193.2Moderate
203.2Moderate
213.2Moderate
223.2Moderate
233.1Moderate
243.1Moderate
253.1Moderate
263.1Moderate
273.1Moderate
283.1Moderate
293.1Moderate
303.1Moderate
313.1Moderate
Planning a trip in May

Is May a good time to visit Castro?

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

6.5
Sightseeing
5th-best month of the year
3.6
Beach & pool
10th-best month of the year

May is a reasonable time to visit Castro for sightseeing.

What to pack for Castro in May

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

In May, Castro sees daytime highs around 20°C and nights near 12°C. Worth packing: rain gear. About 9 days see rain.

rain gear

UV index in Castro in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Castro peaks around January 19 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 13 at about 5 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighExtremeJan 19UV 15Jul 13UV 5
UV index (midday)Level
Jan15Extreme
Feb15Extreme
Mar12Extreme
Apr9Very high
May7High
Jun6High
Jul5High
Aug7High
Sep5High
Oct11Extreme
Nov14Extreme
Dec14Extreme

Air quality in Castro 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 Castro is worst in September — around 17 µg/m³ PM2.5 (moderate), about 2.6× the cleanest month (March, 6 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 1316 µg/m³Mar 136 µg/m³
PM2.5 (µg/m³)Level
Jan7Good
Feb7Good
Mar6Good
Apr7Good
May8Good
Jun8Good
Jul10Good
Aug14Moderate
Sep17Moderate
Oct10Good
Nov7Good
Dec7Good
Location & terrain

Where is Castro?

Castro sits at 24.8°S, 50.0°W, 986 m above sea level, in Brazil. The nearest listed city is Piraí do Sul, 30 km away.

Topography around Castro

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

Within 3 km, the terrain around Castro has only modest variations in elevation — a maximum elevation change of 151 m around an average of 1,004 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 304 m; within 80 km, large variations in elevation — a maximum elevation change of 1,128 m.

The land around Castro is covered by trees (42%), artificial surfaces (28%) and grassland (20%) within 3 km, trees (42%) and cropland (42%) within 16 km, and trees (58%) and cropland (30%) within 80 km.

3 km
151 m
16 km
304 m
80 km
1,128 m
treesgrasslandcroplandartificial surfaceswater
May weather nearby: Piraí do Sul 30 km · Ponta Grossa 37 km · Tibagi 51 km · Jaguariaíva 68 km · Palmeira 71 km · Arapoti 73 km · Cerro Azul 76 km · Imbituva 77 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 Castro (-24.7893°, -50.0123°, elevation 986 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).