Climate and average weather in São Borja

In São Borja, the summers are humid, hot, showery, and partly cloudy and the winters are mild and mostly clear.

Best: late March to mid November

Over the course of the year, the temperature in São Borja typically varies from 11°C to 32°C, and is rarely below 3°C or above 36°C. January is the hottest month of the year, while July is the coldest.

Based on the travel score, the best time of year to visit São Borja for warm-weather activities is from late March to mid November.

Hottest
Jan
32°
Coldest
Jul
11°
Wettest
Oct
210 mm
Driest
Aug
103 mm
Rain / yr
1707 mm
119 wet days
Daylight
10.2–13.8 h
shortest–longest
Elevation
98 m
28.7°S
Clearest
Aug
45% cloud

São Borja is human settlement in Brazil.

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

São Borja 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 March to mid November.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

The hot season lasts 4.2 months, from November 17 to March 25, with daily high temperatures above 29°C. The hottest month of the year in São Borja is January, with an average high of 32°C and low of 22°C.

The cool season lasts 2.9 months, from May 18 to August 14, with daily high temperatures below 22°C. The coldest month of the year in São Borja is July, with an average low of 11°C and high of 20°C.

Days typically run about 10°C warmer than nights year-round.

10°20°30°40°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan3222
Feb3121
Mar3020
Apr2717
May2314
Jun2112
Jul2011
Aug2312
Sep2414
Oct2716
Nov2918
Dec3120

How hot and cold São Borja 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, São Borja feels like about 34°C (around January 6). About 85 days a year carry some heat stress, peaking in January.

10°15°20°25°30°35°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan34322222
Feb33312121
Mar31302020
Apr27271717
May23231414
Jun21211212
Jul20201111
Aug22231212
Sep24241414
Oct27271616
Nov29291818
Dec32312020

Average hourly temperature in São Borja

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 January afternoons, near 32°C, and coldest before dawn in July, near 11°C.

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

São Borja 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
Jan32° / 22°15911.913.63.9
Feb31° / 21°13211.2134.3
Mar30° / 20°12810.212.25.2
Apr27° / 17°16510.111.36.7
May23° / 14°1198.310.67.1
Jun21° / 12°1179.210.26.5
Jul20° / 11°1138.810.46.7
Aug23° / 12°1038.5117.2
Sep24° / 14°15110.111.87.0
Oct27° / 16°21011.512.76.4
Nov29° / 18°155913.45.7
Dec31° / 20°15710.613.84.4

Chance of rain

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

São Borja gets about 1707 mm of precipitation a year. On a typical day the chance of rain is often wet, but that rises and falls sharply with the seasons.

The wetter season lasts 3.1 months, from around Dec 14 to Mar 16, peaking in February at about 40% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Aug 3.

October is the wettest month by volume, with 210 mm over about 12 wet days; August is the driest, with 103 mm.

0%10%20%30%40%50%JanFebMarAprMayJunJulAugSepOctNovDecwetterdriermostly drysome rainoften wetvery wetFeb 21 · 40%Aug 3 · 25%
Rain on a day (%)Rain days
Jan3912
Feb4011
Mar3310
Apr3210
May278
Jun319
Jul289
Aug279
Sep3410
Oct3712
Nov309
Dec3411

Monthly rainfall

Over a full year, São Borja collects about 1707 mm of rain across 119 wet days — roughly 142 mm in an average month.

It doesn’t fall evenly. October is the wettest month with 210 mm, while August is the driest at just 103 mm. The three wettest months alone bring about 31% of the year’s total.

050100150200250JanFebMarAprMayJunJulAugSepOctNovDec159132128165119117113103151210155157
Rainfall (mm)Rain days
Jan15912
Feb13211
Mar12810
Apr16510
May1198
Jun1179
Jul1139
Aug1039
Sep15110
Oct21012
Nov1559
Dec15711

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In São Borja, the average share of the sky covered by clouds shows moderate seasonal variation over the course of the year.

The clearer part of the year begins around November 10 and lasts for 5.1 months, ending around April 12. The clearest month is February, when the sky is clear, mostly clear, or partly cloudy 61% of the time on average.

The cloudier part of the year begins around September 7 and lasts for 2.1 months, ending around November 9. The cloudiest month is October, when it is overcast or mostly cloudy 52% 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%JanFebMarAprMayJunJulAugSepOctNovDecFeb 12 · 62%Oct 13 · 46%clearmostly clearpartly cloudymostly cloudyovercastclearercloudierclearer
Clearer (%)Cloudier (%)
Jan5941
Feb6139
Mar6040
Apr5545
May5149
Jun4852
Jul5644
Aug6040
Sep5446
Oct4852
Nov5743
Dec5941

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 48 min of light; the shortest, around June 7, only 10 h 12 min — a swing of roughly 3 h 36 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan13.67:048:43
Feb13.07:288:29
Mar12.27:478:00
Apr11.38:057:24
May10.68:236:58
Jun10.28:396:50
Jul10.48:397:00
Aug11.08:197:17
Sep11.87:437:33
Oct12.77:087:50
Nov13.46:468:13
Dec13.86:468:35

Sunny days

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

São Borja averages about 13 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 10 and 15 days.

The sunnier stretch runs 1.9 months, from around Jul 14 to Sep 8. The sunniest month is August, with roughly 14 sunny days (mixed).

The greyest month is June, down near 11 sunny days — about 25% fewer than the August peak.

05101520JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedbrightAug 2215 daysJun 2510 days
Sunny daysSky
Jan14Mixed
Feb13Mixed
Mar14Mixed
Apr13Mixed
May12Mixed
Jun11Mixed
Jul13Mixed
Aug15Mixed
Sep13Mixed
Oct11Mixed
Nov13Mixed
Dec14Mixed

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 São Borja, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 6.2 months, from around October 17 to April 23. The muggiest month is February, when the air feels humid, muggy or worse about 90% of the time.

The most comfortable stretch runs from around April 24 to October 16, and July is the most comfortable month — the air is dry or comfortable 81% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecJul 24 · 84%Feb 1 · 8%oppressivemuggycomfortablehumiddryhumidcomfortablehumid
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan391630393
Feb281731393
Mar5122534241
Apr19202226120
May4124191410
Jun522120700
Jul612016300
Aug562219300
Sep4323231000
Oct2324242440
Nov1623272590
Dec7162429232

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.

Across the year, average wind speed in São Borja is typically light breeze, near 12 km/h, and varies little with the seasons.

The windier part of the year lasts 5.7 months, from around Jun 8 to Nov 29. The windiest month is September, averaging about 14 km/h (light breeze).

The calmer part of the year runs from around Nov 30 to Jun 7, with February the calmest month at about 11 km/h.

05101520JanFebMarAprMayJunJulAugSepOctNovDeccalmerwindiercalmercalmlight breezeSep 5 · 14 km/hFeb 26 · 11 km/h
Wind speed (km/h)Feels
Jan12calm
Feb11calm
Mar11calm
Apr11calm
May12calm
Jun13light breeze
Jul13light breeze
Aug14light breeze
Sep14light breeze
Oct14light breeze
Nov13light breeze
Dec12calm

Best time to visit São Borja

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around early November, São Borja 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 São Borja for general outdoor tourist activities is from late March to mid November, with a peak score in the third week of August.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationAug 21 · 7.3

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
Jan3.9fair
Feb4.3fair
Mar5.2fair
Apr6.6good
May7.1good
Jun6.5good
Jul6.7good
Aug7.2good
Sep7.0good
Oct6.4good
Nov5.7good
Dec4.4fair

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 São Borja for hot-weather activities is from late August to mid May, with a peak score in the third week of November.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timebeach/pool scoretemperaturecloudsprecipitationNov 19 · 7.3

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 São Borja, 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.

For a warm-season trip around January (highs near 32°C), the essentials are light clothes, rain gear and sun protection. In the cold season around July (highs near 20°C), pack rain gear.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In January, São Borja sees daytime highs around 32°C and nights near 22°C. Pack light clothes and sun protection. Worth having: rain gear. About 12 days see rain.

UV index (midday) in São Borja 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 São Borja peaks around January 21 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 19 at about 3 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highModerateHighExtremeJan 21UV 14Jun 19UV 3
UV index (midday)Level
Jan14Extreme
Feb13Extreme
Mar11Extreme
Apr8Very high
May5Moderate
Jun3Moderate
Jul4Moderate
Aug5Moderate
Sep8Very high
Oct5High
Nov11Extreme
Dec12Extreme

Average hourly UV index in São Borja

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 January the burn window is concentrated in the middle of the day: about 9 hours a day reach index 3 (protection recommended), and 7 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
Mar7.55.5
Apr6.54
May4.50
Jun2.50
Jul3.50
Aug4.50
Sep6.53
Oct60
Nov8.56
Dec96.5

Air quality in São Borja 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 São Borja is worst in September — around 16 µg/m³ PM2.5 (moderate), about 2.8× the cleanest month (March, 6 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodGoodModerateGoodSep 1116 µg/m³Mar 226 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb14Moderate
Mar6Good
Apr7Good
May6Good
Jun7Good
Jul10Good
Aug15Moderate
Sep16Moderate
Oct9Good
Nov9Good
Dec6Good
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

São Borja 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
Jun990
Jul970
Aug990
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. São Borja banks about 4,125 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around January.

01,0002,0003,0004,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan522
Feb451
Mar459
Apr350
May250
Jun185
Jul167
Aug225
Sep267
Oct354
Nov405
Dec490

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.

São Borja receives about 4.8 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 2.5 and 6.9 kWh/m².

The brighter stretch of the year lasts 6.1 months, from around Sep 23 to Mar 28. The brightest month is December, averaging about 6.9 kWh/m² (intense).

The dimmest month is June, down near 2.5 kWh/m² — roughly 63% less than the December peak.

012345678JanFebMarAprMayJunJulAugSepOctNovDecbrighterdimmerbrighterdimmoderatebrightintenseDec 136.9 kWhJun 232.5 kWh
Solar energy (kWh/m²)Level
Jan6.7Intense
Feb6.0Intense
Mar5.2Bright
Apr4.0Bright
May3.0Moderate
Jun2.5Moderate
Jul2.8Moderate
Aug3.8Moderate
Sep4.6Bright
Oct5.3Bright
Nov6.5Intense
Dec6.9Intense

Where is São Borja?

São Borja sits at 28.7°S, 56.0°W, 98 m above sea level, in Brazil. The nearest listed city is Santo Tomé, 13 km away.

Topography around São Borja

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

Within 3 km, the terrain around São Borja has only modest variations in elevation — a maximum elevation change of 43 m around an average of 79 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 80 m; within 80 km, significant variations in elevation — a maximum elevation change of 276 m.

The land around São Borja is covered by artificial surfaces (26%) and cropland (24%) within 3 km, cropland (47%) within 16 km, and grassland (39%) and cropland (25%) within 80 km.

3 km
43 m
16 km
80 m
80 km
276 m
treesgrasslandcroplandartificial surfaceswaterwetland
Nearby: Santo Tomé 13 km · Gobernador Virasora 68 km · Itaqui 74 km · Apóstoles 87 km · São Luiz Gonzaga 106 km · Santiago 125 km · Alegrete 127 km · São Francisco de Assis 130 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 Borja (-28.6606°, -56.0044°, elevation 98 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).