Climate and average weather in Piraí

In Piraí, the weather is muggy, hot, wet, and partly cloudy and remarkably steady, with daytime highs holding near hot levels all year. The wettest stretch peaks around January.

Best: late April to mid September

Over the course of the year, the temperature in Piraí typically varies from 15°C to 30°C, and is rarely below 12°C or above 34°C. February is the hottest month of the year, while July is the coldest.

Based on the travel score, the best time of year to visit Piraí for warm-weather activities is from late April to mid September.

Hottest
Feb
30°
Coldest
Jul
15°
Wettest
Jan
309 mm
Driest
Aug
37 mm
Rain / yr
1712 mm
183 wet days
Daylight
10.6–13.4 h
shortest–longest
Elevation
381 m
22.6°S
Clearest
Jul
47% cloud

Piraí is human settlement in Brazil.

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

Piraí weather by month, at a glance

The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.

Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around late April to mid September.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

Daily average highs and lows in Piraí, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.

Temperatures in Piraí stay fairly even through the year, without a distinct hot or cool season. The warmest month is February, with an average high of 30°C and low of 22°C; the coolest is July, with an average low of 15°C and high of 24°C.

Days typically run about 8°C warmer than nights year-round.

10°15°20°25°30°35°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan2922
Feb3022
Mar2921
Apr2719
May2517
Jun2416
Jul2415
Aug2516
Sep2617
Oct2719
Nov2720
Dec2821

How hot and cold Piraí really feels

Feels-like highFeels-like lowactual air temp

The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.

On the hottest afternoons, once humidity is folded in, Piraí feels like about 32°C (around February 8). About 33 days a year carry some heat stress, peaking in February.

10°15°20°25°30°35°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan32292222
Feb32302222
Mar31292121
Apr28271919
May25251717
Jun24241616
Jul24241515
Aug25251616
Sep26261717
Oct26271919
Nov27272020
Dec30282121

Average hourly temperature in Piraí

A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on February afternoons, near 30°C, and coldest before dawn in July, near 15°C.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM

Piraí weather by month

Every month at a glance. Click a month for its detailed page.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 22°30923.513.23.6
Feb30° / 22°2221912.83.8
Mar29° / 21°22522.612.24.1
Apr27° / 19°11714.511.55.8
May25° / 17°7011.310.96.7
Jun24° / 16°406.710.67.6
Jul24° / 15°427.410.87.7
Aug25° / 16°37711.27.5
Sep26° / 17°8111.811.96.4
Oct27° / 19°12015.612.55.5
Nov27° / 20°20020.413.14.7
Dec28° / 21°25223.213.44.0

Chance of rain

How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.

Piraí gets about 1712 mm of precipitation a year. On a typical day the chance of rain is very wet, but that rises and falls sharply with the seasons.

The wetter season lasts 5.8 months, from around Oct 19 to Apr 12, peaking in December at about 79% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jun 25.

January is the wettest month by volume, with 309 mm over about 24 wet days; August is the driest, with 37 mm.

0%10%20%30%40%50%60%70%80%90%JanFebMarAprMayJunJulAugSepOctNovDecwetterdrierwettermostly drysome rainoften wetvery wetDec 28 · 79%Jun 25 · 19%
Rain on a day (%)Rain days
Jan7524
Feb6919
Mar7223
Apr4915
May3711
Jun237
Jul237
Aug237
Sep3912
Oct5116
Nov6720
Dec7423

Monthly rainfall

Over a full year, Piraí collects about 1712 mm of rain across 183 wet days — roughly 143 mm in an average month.

It doesn’t fall evenly. January is the wettest month with 309 mm, while August is the driest at just 37 mm. The three wettest months alone bring about 46% of the year’s total.

050100150200250300350JanFebMarAprMayJunJulAugSepOctNovDec3092222251177040423781120200252
Rainfall (mm)Rain days
Jan30924
Feb22219
Mar22523
Apr11715
May7011
Jun407
Jul427
Aug377
Sep8112
Oct12016
Nov20020
Dec25223

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

How often the daytime sky is clear, partly cloudy or overcast.

In Piraí, the average share of the sky covered by clouds shows significant seasonal variation over the course of the year.

The clearer part of the year begins around April 4 and lasts for 5.5 months, ending around September 17. The clearest month is August, when the sky is clear, mostly clear, or partly cloudy 60% of the time on average.

The cloudier part of the year begins around September 18 and lasts for 6.5 months, ending around April 3. The cloudiest month is November, when it is overcast or mostly cloudy 77% of the time.

0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%JanFebMarAprMayJunJulAugSepOctNovDecAug 24 · 61%Dec 5 · 20%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan2872
Feb3565
Mar3763
Apr5050
May5248
Jun5743
Jul5941
Aug6040
Sep4456
Oct2971
Nov2377
Dec2377

Daylight, sunrise and sunset

DaylightNight

Hours of daylight through the year, with sunrise and sunset times.

The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around January 1, brings about 13 h 24 min of light; the shortest, around June 10, only 10 h 36 min — a swing of roughly 2 h 48 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan13.26:277:42
Feb12.86:477:34
Mar12.27:007:10
Apr11.57:126:40
May10.97:246:19
Jun10.67:376:14
Jul10.87:396:23
Aug11.27:236:36
Sep11.96:546:46
Oct12.56:256:57
Nov13.16:087:14
Dec13.46:107:33

Sunny days

How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.

Piraí averages about 8 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 3 and 14 days.

The sunnier stretch runs 5.3 months, from around Apr 13 to Sep 21. The sunniest month is August, with roughly 14 sunny days (mixed).

The greyest month is December, down near 3 sunny days — about 78% fewer than the August peak.

05101520JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedbrightAug 2614 daysDec 33 days
Sunny daysSky
Jan5Gloomy
Feb6Gloomy
Mar6Gloomy
Apr9Mixed
May10Mixed
Jun13Mixed
Jul14Mixed
Aug14Mixed
Sep10Mixed
Oct5Gloomy
Nov3Gloomy
Dec3Gloomy

Humidity comfort

DryComfortableHumidMuggyOppressiveMiserable

Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.

Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.

In Piraí, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 7.1 months, from around October 7 to May 11. The muggiest month is January, when the air feels humid, muggy or worse about 100% of the time.

The most comfortable stretch runs from around May 12 to October 6, and July is the most comfortable month — the air is dry or comfortable 62% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecJul 17 · 66%Jan 1 · 0%oppressivehumidmuggycomfortabledryhumidcomfortablehumid
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
Jan0044453
Feb0044452
Mar0064944
Apr03245716
May32149261
Jun7365070
Jul14493710
Aug14443840
Sep63047170
Oct21535454
Nov06265513
Dec00105436

Wind

Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.

This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.

Wind in Piraí is steady company: average speeds sit near 6 km/hcalm — in every month of the year, with no meaningful windy or calm season.

0510JanFebMarAprMayJunJulAugSepOctNovDeccalmSep 13 · 7 km/hMar 31 · 5 km/h
Wind speed (km/h)Feels
Jan6calm
Feb6calm
Mar5calm
Apr5calm
May5calm
Jun6calm
Jul6calm
Aug6calm
Sep7calm
Oct7calm
Nov6calm
Dec6calm

Hazard calendar for Piraí

In seasonPeak

When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.

Piraí's rainy season runs November–March, when most of the year's rain falls.

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

Best time to visit Piraí

TravelBeach/poolTemperatureCloudsPrecipitation

To characterize how pleasant the weather is in Piraí throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.

Around mid September, Piraí is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.

Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.

The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Piraí for general outdoor tourist activities is from late April to mid September, with a peak score in the last week of June.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationJun 28 · 7.8

The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Travel score (0–10)Rating
Jan3.6fair
Feb3.7fair
Mar4.1fair
Apr5.8good
May6.7good
Jun7.6ideal
Jul7.7ideal
Aug7.5ideal
Sep6.4good
Oct5.5good
Nov4.7fair
Dec4.0fair

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Piraí for hot-weather activities is from early April to late October, with a peak score in the last week of June.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationJun 23 · 6.8

The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

What to pack for Piraí, by month

EssentialRecommendedOptional

Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.

Piraí packs about the same all year — highs hold near 30°C. Across the year the things worth having are light clothes, rain gear and sun protection.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In February, Piraí sees daytime highs around 30°C and nights near 22°C. Pack light clothes and rain gear. Worth having: sun protection. About 19 days see rain.

Sea temperature near Piraí

Average ocean temperature at the nearest coast, month by month, banded into swim-comfort zones — the other half of the beach question.

The sea at the nearest coast (about 55 km away) is warmest in February 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°28°JanFebMarAprMayJunJulAugSepOctNovDeccoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan26Warm
Feb26Warm
Mar26Warm
Apr25Warm
May24Refreshing
Jun23Refreshing
Jul22Refreshing
Aug21Refreshing
Sep21Refreshing
Oct22Refreshing
Nov23Refreshing
Dec24Warm

UV index (midday) in Piraí by month

LowModerateHighVery highExtreme

Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.

Under clear skies, the midday UV index in Piraí peaks around February 9 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 12 at about 5 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighVery highExtremeFeb 9UV 14Jul 12UV 5
UV index (midday)Level
Jan14Extreme
Feb14Extreme
Mar12Extreme
Apr9Very high
May7High
Jun6High
Jul5High
Aug8Very high
Sep7High
Oct11Extreme
Nov13Extreme
Dec14Extreme

Average hourly UV index in Piraí

LowModerateHighVery highExtreme

Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.

The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

UV falls off far faster than brightness as the sun drops, so even in February the burn window is concentrated in the middle of the day: about 8.5 hours a day reach index 3 (protection recommended), and 6.5 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM
UV ≥ 3 (h/day)UV ≥ 6 (h/day)
Jan97
Feb8.56.5
Mar85.5
Apr74.5
May5.52.5
Jun50
Jul50
Aug6.53.5
Sep6.53
Oct85.5
Nov8.56.5
Dec8.57

Air quality in Piraí by month

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.

Air quality in Piraí is worst in September — around 33 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (December, 15 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateSep 1332 µg/m³Dec 2115 µg/m³
PM2.5 (µg/m³)Level
Jan16Moderate
Feb16Moderate
Mar17Moderate
Apr19Moderate
May24Moderate
Jun29Moderate
Jul31Moderate
Aug27Moderate
Sep33Moderate
Oct20Moderate
Nov17Moderate
Dec15Moderate
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Piraí is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecfrost-free year round
Frost-free chance (%)Frost nights
Jan1000
Feb1000
Mar1000
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov1000
Dec1000

Growing degree days

Degree days (base 10°C)Frost-free shaded

Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Piraí banks about 4,596 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around February.

01,0002,0003,0004,0005,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan479
Feb439
Mar456
Apr396
May336
Jun299
Jul296
Aug317
Sep342
Oct389
Nov395
Dec452

Solar energy

Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.

Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.

Piraí receives about 4.6 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 3.3 and 5.8 kWh/m².

The brighter stretch of the year lasts 6.0 months, from around Sep 28 to Mar 30. The brightest month is February, averaging about 5.7 kWh/m² (bright).

The dimmest month is June, down near 3.4 kWh/m² — roughly 41% less than the February peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecbrighterdimmerbrighterdimmoderatebrightintenseFeb 55.8 kWhJun 13.3 kWh
Solar energy (kWh/m²)Level
Jan5.6Bright
Feb5.8Bright
Mar4.9Bright
Apr4.3Bright
May3.6Moderate
Jun3.4Moderate
Jul3.5Moderate
Aug4.2Bright
Sep4.5Bright
Oct5.0Bright
Nov5.1Bright
Dec5.6Bright

Where is Piraí?

Piraí sits at 22.6°S, 43.9°W, 381 m above sea level, in Brazil. The nearest listed city is Pinheiral, 17 km away.

Topography around Piraí

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

Within 3 km, the terrain around Piraí has only modest variations in elevation — a maximum elevation change of 209 m around an average of 430 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 806 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,556 m.

The land around Piraí is covered by trees (51%) and grassland (37%) within 3 km, trees (53%) and grassland (43%) within 16 km, and trees (43%), grassland (31%) and water (20%) within 80 km.

3 km
209 m
16 km
806 m
80 km
2,556 m
treesgrasslandartificial surfaceswater
Nearby: Pinheiral 17 km · Barra do Piraí 19 km · Paracambi 19 km · Mendes 20 km · Seropédica 23 km · Volta Redonda 24 km · Japeri 25 km · Universidade Rural 26 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 Piraí (-22.6292°, -43.8981°, elevation 381 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).