Climate and average weather in Riachão
In Riachão, the weather is sweltering, wet, and mostly clear and remarkably steady, with daytime highs holding near sweltering levels all year. The wettest stretch peaks around January.
Over the course of the year, the temperature in Riachão typically varies from 22°C to 35°C, and is rarely below 20°C or above 37°C. September is the hottest month of the year, while January is the coldest.
Based on the travel score, the best time of year to visit Riachão for warm-weather activities is from late April to mid August.
- Hottest
- Sep
- 35°
- Coldest
- Jan
- 22°
- Wettest
- Jan
- 308 mm
- Driest
- Jul
- 1 mm
- Rain / yr
- 1575 mm
- 161 wet days
- Daylight
- 11.6–12.4 h
- shortest–longest
- Elevation
- 385 m
- 7.4°S
- Clearest
- Aug
- 25% cloud
Riachão is settlement in Brazil.
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Riachão 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 August.
Temperature through the year
Daily average highs and lows in Riachão, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
Temperatures in Riachão stay fairly even through the year, without a distinct hot or cool season. The warmest month is September, with an average high of 35°C and low of 23°C; the coolest is January, with an average low of 22°C and high of 30°C.
Days typically run about 10°C warmer than nights, with the widest day–night swing (around 12°C) in August.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 30 | 30 | 30 | 31 | 31 | 32 | 33 | 34 | 35 | 33 | 31 | 30 |
| Avg low (°C) | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 23 | 23 | 22 | 22 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| Jan | 30 | 22 |
| Feb | 30 | 22 |
| Mar | 30 | 22 |
| Apr | 31 | 22 |
| May | 31 | 22 |
| Jun | 32 | 22 |
| Jul | 33 | 22 |
| Aug | 34 | 22 |
| Sep | 35 | 23 |
| Oct | 33 | 23 |
| Nov | 31 | 22 |
| Dec | 30 | 22 |
How hot and cold Riachão really feels
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, Riachão feels like about 35°C (around October 3). Nearly every day a year carries some heat stress, peaking in October.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels-like high (°C) | 33 | 33 | 34 | 34 | 34 | 33 | 33 | 34 | 35 | 35 | 34 | 34 |
| Air high (°C) | 30 | 30 | 30 | 31 | 31 | 32 | 33 | 34 | 35 | 33 | 31 | 30 |
| Feels-like low (°C) | 21 | 22 | 22 | 22 | 22 | 22 | 21 | 22 | 23 | 23 | 22 | 22 |
| Air low (°C) | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 23 | 23 | 22 | 22 |
| Feels-like high (°C) | Air high (°C) | Feels-like low (°C) | Air low (°C) | |
|---|---|---|---|---|
| Jan | 33 | 30 | 21 | 22 |
| Feb | 33 | 30 | 22 | 22 |
| Mar | 34 | 30 | 22 | 22 |
| Apr | 34 | 31 | 22 | 22 |
| May | 34 | 31 | 22 | 22 |
| Jun | 33 | 32 | 22 | 22 |
| Jul | 33 | 33 | 21 | 22 |
| Aug | 34 | 34 | 22 | 22 |
| Sep | 35 | 35 | 23 | 23 |
| Oct | 35 | 33 | 23 | 23 |
| Nov | 34 | 31 | 22 | 22 |
| Dec | 34 | 30 | 22 | 22 |
Average hourly temperature in Riachão
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 September afternoons, near 35°C, and coldest before dawn in January, near 22°C.
Riachão weather by month
Every month at a glance. Click a month for its detailed page.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 30° / 22° | 308 | 27.2 | 12.4 | 3.0 |
| Feb | 30° / 22° | 268 | 24.5 | 12.2 | 3.0 |
| Mar | 30° / 22° | 272 | 26.7 | 12 | 3.0 |
| Apr | 31° / 22° | 149 | 18.4 | 11.8 | 3.7 |
| May | 31° / 22° | 56 | 8.6 | 11.7 | 4.4 |
| Jun | 32° / 22° | 4 | 0.6 | 11.6 | 5.0 |
| Jul | 33° / 22° | 1 | 0.2 | 11.6 | 4.8 |
| Aug | 34° / 22° | 2 | 0.4 | 11.8 | 4.0 |
| Sep | 35° / 23° | 16 | 2.7 | 12 | 3.2 |
| Oct | 33° / 23° | 86 | 9.9 | 12.2 | 3.4 |
| Nov | 31° / 22° | 185 | 18.3 | 12.3 | 3.5 |
| Dec | 30° / 22° | 227 | 23.5 | 12.4 | 3.3 |
Chance of rain
How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.
Riachão gets about 1575 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 6.1 months, from around Oct 27 to Apr 30, peaking in February at about 88% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jul 30.
January is the wettest month by volume, with 308 mm over about 27 wet days; July is the driest, with 1 mm.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain on a day (%) | 87 | 87 | 86 | 62 | 27 | 3 | 1 | 1 | 9 | 32 | 61 | 77 |
| Rain days | 27 | 25 | 27 | 18 | 9 | 1 | 0 | 0 | 3 | 10 | 18 | 24 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 87 | 27 |
| Feb | 87 | 25 |
| Mar | 86 | 27 |
| Apr | 62 | 18 |
| May | 27 | 9 |
| Jun | 3 | 1 |
| Jul | 1 | 0 |
| Aug | 1 | 0 |
| Sep | 9 | 3 |
| Oct | 32 | 10 |
| Nov | 61 | 18 |
| Dec | 77 | 24 |
Monthly rainfall
Over a full year, Riachão collects about 1575 mm of rain across 161 wet days — roughly 131 mm in an average month.
It doesn’t fall evenly. January is the wettest month with 308 mm, while July is the driest at just 1 mm. The three wettest months alone bring about 54% of the year’s total.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rainfall (mm) | 308 | 268 | 272 | 149 | 56 | 4 | 1 | 2 | 16 | 86 | 185 | 227 |
| Rain days | 27 | 25 | 27 | 18 | 9 | 1 | 0 | 0 | 3 | 10 | 18 | 24 |
| Rainfall (mm) | Rain days | |
|---|---|---|
| Jan | 308 | 27 |
| Feb | 268 | 25 |
| Mar | 272 | 27 |
| Apr | 149 | 18 |
| May | 56 | 9 |
| Jun | 4 | 1 |
| Jul | 1 | 0 |
| Aug | 2 | 0 |
| Sep | 16 | 3 |
| Oct | 86 | 10 |
| Nov | 185 | 18 |
| Dec | 227 | 24 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Riachão, 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 May 12 and lasts for 5.5 months, ending around October 24. The clearest month is July, when the sky is clear, mostly clear, or partly cloudy 90% of the time on average.
The cloudier part of the year begins around October 25 and lasts for 6.5 months, ending around May 11. The cloudiest month is February, when it is overcast or mostly cloudy 86% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 15 | 14 | 16 | 32 | 53 | 81 | 90 | 90 | 81 | 56 | 31 | 22 |
| Cloudier (%) | 85 | 86 | 84 | 68 | 47 | 19 | 10 | 10 | 19 | 44 | 69 | 78 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 15 | 85 |
| Feb | 14 | 86 |
| Mar | 16 | 84 |
| Apr | 32 | 68 |
| May | 53 | 47 |
| Jun | 81 | 19 |
| Jul | 90 | 10 |
| Aug | 90 | 10 |
| Sep | 81 | 19 |
| Oct | 56 | 44 |
| Nov | 31 | 69 |
| Dec | 22 | 78 |
Daylight, sunrise and sunset
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 12 h 24 min of light; the shortest, around May 20, only 11 h 36 min — a swing of roughly 0 h 48 min.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 12.4 | 12.2 | 12.0 | 11.8 | 11.7 | 11.6 | 11.6 | 11.8 | 12.0 | 12.2 | 12.3 | 12.4 |
| Sunrise (AM) | 6:04 | 6:14 | 6:15 | 6:12 | 6:13 | 6:19 | 6:24 | 6:18 | 6:02 | 5:47 | 5:41 | 5:50 |
| Sunset (PM) | 6:27 | 6:28 | 6:18 | 6:02 | 5:53 | 5:54 | 6:00 | 6:03 | 6:00 | 5:56 | 6:02 | 6:15 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 12.4 | 6:04 | 6:27 |
| Feb | 12.2 | 6:14 | 6:28 |
| Mar | 12.0 | 6:15 | 6:18 |
| Apr | 11.8 | 6:12 | 6:02 |
| May | 11.7 | 6:13 | 5:53 |
| Jun | 11.6 | 6:19 | 5:54 |
| Jul | 11.6 | 6:24 | 6:00 |
| Aug | 11.8 | 6:18 | 6:03 |
| Sep | 12.0 | 6:02 | 6:00 |
| Oct | 12.2 | 5:47 | 5:56 |
| Nov | 12.3 | 5:41 | 6:02 |
| Dec | 12.4 | 5:50 | 6:15 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Riachão averages about 10 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 1 and 25 days.
The sunnier stretch runs 5.1 months, from around May 19 to Oct 19. The sunniest month is July, with roughly 23 sunny days (brilliant).
The greyest month is January, down near 1 sunny days — about 94% fewer than the July peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 1 | 1 | 1 | 4 | 10 | 18 | 24 | 24 | 20 | 12 | 4 | 3 |
| Sky | Gloomy | Gloomy | Gloomy | Gloomy | Mixed | Bright | Brilliant | Brilliant | Bright | Mixed | Gloomy | Gloomy |
| Sunny days | Sky | |
|---|---|---|
| Jan | 1 | Gloomy |
| Feb | 1 | Gloomy |
| Mar | 1 | Gloomy |
| Apr | 4 | Gloomy |
| May | 10 | Mixed |
| Jun | 18 | Bright |
| Jul | 24 | Brilliant |
| Aug | 24 | Brilliant |
| Sep | 20 | Bright |
| Oct | 12 | Mixed |
| Nov | 4 | Gloomy |
| Dec | 3 | Gloomy |
Humidity comfort
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 Riachão, how humid it feels changes dramatically over the year.
The more humid part of the year lasts 8.5 months, from around October 4 to June 18. 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 June 19 to October 3, and August is the most comfortable month — the air is dry or comfortable 71% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 0 | 0 | 0 | 0 | 0 | 0 | 5 | 13 | 8 | 0 | 0 | 0 |
| Comfortable (%) | 0 | 0 | 0 | 0 | 0 | 14 | 46 | 59 | 37 | 8 | 0 | 0 |
| Humid (%) | 0 | 0 | 0 | 0 | 11 | 56 | 41 | 23 | 29 | 22 | 4 | 0 |
| Muggy (%) | 8 | 8 | 5 | 14 | 47 | 26 | 7 | 5 | 22 | 37 | 23 | 13 |
| Oppressive (%) | 92 | 92 | 95 | 85 | 42 | 4 | 0 | 0 | 5 | 32 | 73 | 87 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | Oppressive (%) | |
|---|---|---|---|---|---|
| Jan | 0 | 0 | 0 | 8 | 92 |
| Feb | 0 | 0 | 0 | 8 | 92 |
| Mar | 0 | 0 | 0 | 5 | 95 |
| Apr | 0 | 0 | 0 | 14 | 85 |
| May | 0 | 0 | 11 | 47 | 42 |
| Jun | 0 | 14 | 56 | 26 | 4 |
| Jul | 5 | 46 | 41 | 7 | 0 |
| Aug | 13 | 59 | 23 | 5 | 0 |
| Sep | 8 | 37 | 29 | 22 | 5 |
| Oct | 0 | 8 | 22 | 37 | 32 |
| Nov | 0 | 0 | 4 | 23 | 73 |
| Dec | 0 | 0 | 0 | 13 | 87 |
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 Riachão is typically calm, near 8 km/h, and varies moderately with the seasons.
The windier part of the year lasts 5.1 months, from around May 12 to Oct 12. The windiest month is July, averaging about 11 km/h (calm).
The calmer part of the year runs from around Oct 13 to May 11, with January the calmest month at about 6 km/h.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 6 | 6 | 6 | 6 | 8 | 11 | 11 | 11 | 10 | 8 | 6 | 6 |
| Feels | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (km/h) | Feels | |
|---|---|---|
| Jan | 6 | calm |
| Feb | 6 | calm |
| Mar | 6 | calm |
| Apr | 6 | calm |
| May | 8 | calm |
| Jun | 11 | calm |
| Jul | 11 | calm |
| Aug | 11 | calm |
| Sep | 10 | calm |
| Oct | 8 | calm |
| Nov | 6 | calm |
| Dec | 6 | calm |
Hazard calendar for Riachão
When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.
Riachão's monsoon runs November–April, when most of the year's rain falls.
Best time to visit Riachão
To characterize how pleasant the weather is in Riachão throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around early August, Riachão 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 Riachão for general outdoor tourist activities is from late April to mid August, with a peak score in the third week of June.
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).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Travel score (0–10) | 3.0 | 3.0 | 3.0 | 3.7 | 4.4 | 5.0 | 4.8 | 4.0 | 3.3 | 3.4 | 3.5 | 3.2 |
| Rating | poor | poor | poor | fair | fair | fair | fair | fair | poor | poor | poor | poor |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 3.0 | poor |
| Feb | 3.0 | poor |
| Mar | 3.0 | poor |
| Apr | 3.7 | fair |
| May | 4.4 | fair |
| Jun | 5.0 | fair |
| Jul | 4.8 | fair |
| Aug | 4.0 | fair |
| Sep | 3.3 | poor |
| Oct | 3.4 | poor |
| Nov | 3.5 | poor |
| Dec | 3.2 | poor |
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 Riachão for hot-weather activities is from mid May to early October, with a peak score in the first week of July.
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 Riachão, by month
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.
Riachão packs about the same all year — highs hold near 35°C. Across the year the things worth having are light clothes, sun protection and rain gear.
In September, Riachão sees daytime highs around 35°C and nights near 23°C. Pack light clothes and sun protection.
UV index (midday) in Riachão by month
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 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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 14 | 15 | 15 | 14 | 11 | 10 | 10 | 11 | 12 | 12 | 12 | 11 |
| Level | Extreme | Extreme | Extreme | Extreme | Extreme | Very high | Very high | Extreme | Extreme | Extreme | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 14 | Extreme |
| Feb | 15 | Extreme |
| Mar | 15 | Extreme |
| Apr | 14 | Extreme |
| May | 11 | Extreme |
| Jun | 10 | Very high |
| Jul | 10 | Very high |
| Aug | 11 | Extreme |
| Sep | 12 | Extreme |
| Oct | 12 | Extreme |
| Nov | 12 | Extreme |
| Dec | 11 | Extreme |
Average hourly UV index in Riachão
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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV ≥ 3 (h/day) | 8.5 | 8.5 | 8.5 | 8 | 7.5 | 7 | 7.5 | 7.5 | 8 | 8 | 8 | 8 |
| UV ≥ 6 (h/day) | 6.5 | 6.5 | 6.5 | 6 | 5.5 | 5 | 5 | 5.5 | 6 | 6 | 6 | 6 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 8.5 | 6.5 |
| Feb | 8.5 | 6.5 |
| Mar | 8.5 | 6.5 |
| Apr | 8 | 6 |
| May | 7.5 | 5.5 |
| Jun | 7 | 5 |
| Jul | 7.5 | 5 |
| Aug | 7.5 | 5.5 |
| Sep | 8 | 6 |
| Oct | 8 | 6 |
| Nov | 8 | 6 |
| Dec | 8 | 6 |
Air quality in Riachão by month
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 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).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 12 | 11 | 11 | 11 | 7 | 6 | 7 | 15 | 30 | 26 | 17 | 14 |
| Level | Good | Good | Good | Good | Good | Good | Good | Moderate | Moderate | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 12 | Good |
| Feb | 11 | Good |
| Mar | 11 | Good |
| Apr | 11 | Good |
| May | 7 | Good |
| Jun | 6 | Good |
| Jul | 7 | Good |
| Aug | 15 | Moderate |
| Sep | 30 | Moderate |
| Oct | 26 | Moderate |
| Nov | 17 | Moderate |
| Dec | 14 | Moderate |
Growing season
Riachão is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |
| Frost nights | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 100 | 0 |
| Feb | 100 | 0 |
| Mar | 100 | 0 |
| Apr | 100 | 0 |
| May | 100 | 0 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 100 | 0 |
| Oct | 100 | 0 |
| Nov | 100 | 0 |
| Dec | 100 | 0 |
Growing degree days
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. Riachão banks about 6,120 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around September.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Growing degree days (°C·days) | 483 | 438 | 489 | 482 | 516 | 509 | 529 | 558 | 565 | 557 | 498 | 496 |
| Growing degree days (°C·days) | |
|---|---|
| Jan | 483 |
| Feb | 438 |
| Mar | 489 |
| Apr | 482 |
| May | 516 |
| Jun | 509 |
| Jul | 529 |
| Aug | 558 |
| Sep | 565 |
| Oct | 557 |
| Nov | 498 |
| Dec | 496 |
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.
Riachão receives about 5.5 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 4.8 and 6.6 kWh/m².
The brighter stretch of the year lasts 4.6 months, from around Jun 30 to Nov 15. The brightest month is September, averaging about 6.5 kWh/m² (intense).
The dimmest month is March, down near 4.9 kWh/m² — roughly 25% less than the September peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 4.9 | 5.0 | 4.9 | 5.0 | 5.1 | 5.4 | 5.7 | 6.3 | 6.5 | 6.2 | 5.5 | 5.1 |
| Level | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Intense | Intense | Intense | Bright | Bright |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 4.9 | Bright |
| Feb | 5.0 | Bright |
| Mar | 4.9 | Bright |
| Apr | 5.0 | Bright |
| May | 5.1 | Bright |
| Jun | 5.4 | Bright |
| Jul | 5.7 | Bright |
| Aug | 6.3 | Intense |
| Sep | 6.5 | Intense |
| Oct | 6.2 | Intense |
| Nov | 5.5 | Bright |
| Dec | 5.1 | Bright |
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.
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
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).