Riachão weather in September
In September, Riachão sees average daytime highs of 35°C and overnight lows near 23°C, with 16 mm of rain across 2.7 wet days and about 12 hours of daylight. It is the 1st-warmest and 9th-wettest month of the year here.
Day-to-day highs hold fairly steady near 35°C through the month. The sky is clear or mostly clear about 66% of the time in September, and the air most often feels comfortable.
Daylight stretches from about 11 h 54 min at the start of September to 12 h 06 min by month's end. Set against the rest of the year, September is Riachão's 3rd-clearest and 4th-windiest month. For the whole year in context, see Riachão's year-round climate.
- Daytime high
- 35°
- 1st warmest
- Overnight low
- 23°
- 12th coldest
- Rainfall
- 16 mm
- 2.7 wet days
- Daylight
- 12 hours
- 6:02 AM – 6:00 PM
- Cloud cover
- 35%
- 3rd clearest
- Wind
- 10 km/h
- 4th windiest
- Solar energy
- 6.55 kWh/m²
- Travel score
- 3.2
- out of 10
Riachão is settlement in Brazil.
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Temperature in September
Day-to-day highs hold fairly steady near 35°C through the month.
A typical September day in Riachão reaches about 35°C in the afternoon and slips back to 23°C overnight — a 12°C spread between the day's warmth and the night's chill. On most days the high lands between 32°C and 37°C. Set against its neighbours, September runs on par with August and about 2°C warmer than October.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 35 | 34 | 34 | 34 | 34 |
| Avg low (°C) | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| 1 | 35 | 23 |
| 2 | 35 | 23 |
| 3 | 35 | 23 |
| 4 | 35 | 23 |
| 5 | 35 | 23 |
| 6 | 35 | 23 |
| 7 | 35 | 23 |
| 8 | 35 | 23 |
| 9 | 35 | 23 |
| 10 | 35 | 23 |
| 11 | 35 | 23 |
| 12 | 35 | 23 |
| 13 | 35 | 23 |
| 14 | 35 | 23 |
| 15 | 35 | 23 |
| 16 | 35 | 23 |
| 17 | 35 | 23 |
| 18 | 35 | 23 |
| 19 | 35 | 23 |
| 20 | 35 | 23 |
| 21 | 35 | 23 |
| 22 | 35 | 23 |
| 23 | 35 | 23 |
| 24 | 35 | 23 |
| 25 | 35 | 23 |
| 26 | 35 | 23 |
| 27 | 34 | 23 |
| 28 | 34 | 23 |
| 29 | 34 | 23 |
| 30 | 34 | 23 |
How September really feels in Riachão
Once humidity and wind are folded in, September averages 30 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.
The story in September is heat — humidity pushes the afternoon "feels like" well above the raw temperature.
Riachão weather by month
How September compares with the rest of the year at a glance. September is the 1st-warmest and 9th-wettest month here — the current month is highlighted below.
| 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 |
Cloud cover in September
The sky is clear or mostly clear about 66% of the time in September.
Beyond those clear spells, partly cloudy skies cover about 16% of September, with mostly cloudy or overcast conditions the remaining 18%. Skies tend to cloud over as the month goes on.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 88 | 88 | 88 | 88 | 88 | 88 | 87 | 87 | 87 | 86 | 86 | 86 | 86 | 85 | 85 | 84 | 83 | 82 | 81 | 80 | 79 | 77 | 76 | 75 | 74 | 73 | 72 | 70 | 70 | 69 |
| Cloudier (%) | 12 | 12 | 12 | 12 | 12 | 12 | 13 | 13 | 13 | 14 | 14 | 14 | 14 | 15 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 23 | 24 | 25 | 26 | 27 | 28 | 30 | 30 | 31 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| 1 | 88 | 12 |
| 2 | 88 | 12 |
| 3 | 88 | 12 |
| 4 | 88 | 12 |
| 5 | 88 | 12 |
| 6 | 88 | 12 |
| 7 | 87 | 13 |
| 8 | 87 | 13 |
| 9 | 87 | 13 |
| 10 | 86 | 14 |
| 11 | 86 | 14 |
| 12 | 86 | 14 |
| 13 | 86 | 14 |
| 14 | 85 | 15 |
| 15 | 85 | 15 |
| 16 | 84 | 16 |
| 17 | 83 | 17 |
| 18 | 82 | 18 |
| 19 | 81 | 19 |
| 20 | 80 | 20 |
| 21 | 79 | 21 |
| 22 | 77 | 23 |
| 23 | 76 | 24 |
| 24 | 75 | 25 |
| 25 | 74 | 26 |
| 26 | 73 | 27 |
| 27 | 72 | 28 |
| 28 | 70 | 30 |
| 29 | 70 | 30 |
| 30 | 69 | 31 |
Chance of precipitation in September
Riachão gets around 16 mm of rain over 2.7 wet days in September. The line is the day-by-day chance of measurable precipitation.
Day to day, the chance of measurable rain averages around 9% and peaks near 18% on the wettest days. The odds climb toward the end of the month.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain chance (%) | 3 | 3 | 4 | 4 | 4 | 4 | 4 | 5 | 5 | 5 | 5 | 6 | 6 | 7 | 7 | 8 | 9 | 10 | 10 | 11 | 12 | 13 | 13 | 14 | 15 | 16 | 16 | 17 | 18 | 18 |
| Rain chance (%) | |
|---|---|
| 1 | 3 |
| 2 | 3 |
| 3 | 4 |
| 4 | 4 |
| 5 | 4 |
| 6 | 4 |
| 7 | 4 |
| 8 | 5 |
| 9 | 5 |
| 10 | 5 |
| 11 | 5 |
| 12 | 6 |
| 13 | 6 |
| 14 | 7 |
| 15 | 7 |
| 16 | 8 |
| 17 | 9 |
| 18 | 10 |
| 19 | 10 |
| 20 | 11 |
| 21 | 12 |
| 22 | 13 |
| 23 | 13 |
| 24 | 14 |
| 25 | 15 |
| 26 | 16 |
| 27 | 16 |
| 28 | 17 |
| 29 | 18 |
| 30 | 18 |
Humidity in September
Most of September feels comfortable — the stacked bands show each day's mix of comfort levels, read off the dew point.
By dew point, September lands in the comfortable band about 37% of days. Sticky, muggy-or-worse air turns up on roughly 26% of them.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 11 | 11 | 11 | 10 | 10 | 10 | 9 | 9 | 8 | 8 | 7 | 7 | 6 | 5 | 5 | 4 | 4 | 3 | 3 | 2 | 2 |
| Comfortable (%) | 50 | 50 | 49 | 48 | 48 | 47 | 47 | 46 | 45 | 45 | 44 | 44 | 43 | 42 | 42 | 40 | 39 | 37 | 36 | 34 | 31 | 29 | 27 | 25 | 23 | 22 | 20 | 19 | 17 | 16 |
| Humid (%) | 25 | 25 | 26 | 26 | 26 | 27 | 27 | 27 | 27 | 27 | 28 | 28 | 28 | 28 | 28 | 28 | 29 | 29 | 29 | 30 | 30 | 30 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 |
| Muggy (%) | 12 | 12 | 13 | 13 | 13 | 14 | 14 | 14 | 14 | 15 | 15 | 16 | 17 | 17 | 18 | 19 | 20 | 21 | 22 | 24 | 25 | 27 | 29 | 30 | 32 | 33 | 35 | 36 | 37 | 37 |
| Oppressive (%) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 2 | 2 | 3 | 3 | 4 | 4 | 5 | 6 | 7 | 7 | 8 | 9 | 9 | 10 | 11 | 12 | 12 | 13 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | Oppressive (%) | |
|---|---|---|---|---|---|
| 1 | 12 | 50 | 25 | 12 | 1 |
| 2 | 12 | 50 | 25 | 12 | 1 |
| 3 | 12 | 49 | 26 | 13 | 1 |
| 4 | 12 | 48 | 26 | 13 | 1 |
| 5 | 12 | 48 | 26 | 13 | 1 |
| 6 | 12 | 47 | 27 | 14 | 1 |
| 7 | 12 | 47 | 27 | 14 | 1 |
| 8 | 12 | 46 | 27 | 14 | 1 |
| 9 | 12 | 45 | 27 | 14 | 1 |
| 10 | 11 | 45 | 27 | 15 | 1 |
| 11 | 11 | 44 | 28 | 15 | 1 |
| 12 | 11 | 44 | 28 | 16 | 2 |
| 13 | 10 | 43 | 28 | 17 | 2 |
| 14 | 10 | 42 | 28 | 17 | 2 |
| 15 | 10 | 42 | 28 | 18 | 3 |
| 16 | 9 | 40 | 28 | 19 | 3 |
| 17 | 9 | 39 | 29 | 20 | 4 |
| 18 | 8 | 37 | 29 | 21 | 4 |
| 19 | 8 | 36 | 29 | 22 | 5 |
| 20 | 7 | 34 | 30 | 24 | 6 |
| 21 | 7 | 31 | 30 | 25 | 7 |
| 22 | 6 | 29 | 30 | 27 | 7 |
| 23 | 5 | 27 | 31 | 29 | 8 |
| 24 | 5 | 25 | 31 | 30 | 9 |
| 25 | 4 | 23 | 31 | 32 | 9 |
| 26 | 4 | 22 | 31 | 33 | 10 |
| 27 | 3 | 20 | 31 | 35 | 11 |
| 28 | 3 | 19 | 31 | 36 | 12 |
| 29 | 2 | 17 | 31 | 37 | 12 |
| 30 | 2 | 16 | 31 | 37 | 13 |
Wind in September
Winds average 10 km/h in September.
Across September, daily wind ranges from about 9 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 |
| Feels | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (km/h) | Feels | |
|---|---|---|
| 1 | 11 | calm |
| 2 | 11 | calm |
| 3 | 11 | calm |
| 4 | 11 | calm |
| 5 | 11 | calm |
| 6 | 11 | calm |
| 7 | 11 | calm |
| 8 | 11 | calm |
| 9 | 11 | calm |
| 10 | 11 | calm |
| 11 | 11 | calm |
| 12 | 11 | calm |
| 13 | 11 | calm |
| 14 | 10 | calm |
| 15 | 10 | calm |
| 16 | 10 | calm |
| 17 | 10 | calm |
| 18 | 10 | calm |
| 19 | 10 | calm |
| 20 | 10 | calm |
| 21 | 10 | calm |
| 22 | 9 | calm |
| 23 | 9 | calm |
| 24 | 9 | calm |
| 25 | 9 | calm |
| 26 | 9 | calm |
| 27 | 9 | calm |
| 28 | 9 | calm |
| 29 | 9 | calm |
| 30 | 9 | calm |
Sunrise & sunset in September
Daylight runs from about 11 h 54 min at the start of September to 12 h 06 min by month's end. The lit band spans sunrise to sunset each day.
Days grow by about 12 minutes over September. Sunrise moves from 6:10 AM to 5:54 AM, and sunset from 6:02 PM to 5:57 PM.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 11.9 | 11.9 | 11.9 | 11.9 | 11.9 | 11.9 | 11.9 | 11.9 | 11.9 | 11.9 | 11.9 | 11.9 | 11.9 | 11.9 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.1 | 12.1 |
| Sunrise (AM) | 6:10 | 6:10 | 6:09 | 6:09 | 6:08 | 6:08 | 6:07 | 6:07 | 6:06 | 6:05 | 6:05 | 6:04 | 6:04 | 6:03 | 6:03 | 6:02 | 6:01 | 6:01 | 6:00 | 6:00 | 5:59 | 5:59 | 5:58 | 5:57 | 5:57 | 5:56 | 5:56 | 5:55 | 5:55 | 5:54 |
| Sunset (PM) | 6:02 | 6:02 | 6:02 | 6:01 | 6:01 | 6:01 | 6:01 | 6:01 | 6:01 | 6:01 | 6:00 | 6:00 | 6:00 | 6:00 | 6:00 | 6:00 | 5:59 | 5:59 | 5:59 | 5:59 | 5:59 | 5:59 | 5:58 | 5:58 | 5:58 | 5:58 | 5:58 | 5:58 | 5:58 | 5:57 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| 1 | 11.9 | 6:10 | 6:02 |
| 2 | 11.9 | 6:10 | 6:02 |
| 3 | 11.9 | 6:09 | 6:02 |
| 4 | 11.9 | 6:09 | 6:01 |
| 5 | 11.9 | 6:08 | 6:01 |
| 6 | 11.9 | 6:08 | 6:01 |
| 7 | 11.9 | 6:07 | 6:01 |
| 8 | 11.9 | 6:07 | 6:01 |
| 9 | 11.9 | 6:06 | 6:01 |
| 10 | 11.9 | 6:05 | 6:01 |
| 11 | 11.9 | 6:05 | 6:00 |
| 12 | 11.9 | 6:04 | 6:00 |
| 13 | 11.9 | 6:04 | 6:00 |
| 14 | 11.9 | 6:03 | 6:00 |
| 15 | 12.0 | 6:03 | 6:00 |
| 16 | 12.0 | 6:02 | 6:00 |
| 17 | 12.0 | 6:01 | 5:59 |
| 18 | 12.0 | 6:01 | 5:59 |
| 19 | 12.0 | 6:00 | 5:59 |
| 20 | 12.0 | 6:00 | 5:59 |
| 21 | 12.0 | 5:59 | 5:59 |
| 22 | 12.0 | 5:59 | 5:59 |
| 23 | 12.0 | 5:58 | 5:58 |
| 24 | 12.0 | 5:57 | 5:58 |
| 25 | 12.0 | 5:57 | 5:58 |
| 26 | 12.0 | 5:56 | 5:58 |
| 27 | 12.0 | 5:56 | 5:58 |
| 28 | 12.0 | 5:55 | 5:58 |
| 29 | 12.1 | 5:55 | 5:58 |
| 30 | 12.1 | 5:54 | 5:57 |
Solar energy in September
Average shortwave solar energy reaching the ground each day in September, about 6.55 kWh/m² — the sunniest month for solar.
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 — September's 6.55 kWh/m² sits near the top of that range.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.6 | 6.6 | 6.6 | 6.6 | 6.6 | 6.6 | 6.6 | 6.6 | 6.6 | 6.6 | 6.6 | 6.6 | 6.6 | 6.6 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.4 |
| Level | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| 1 | 6.5 | Intense |
| 2 | 6.5 | Intense |
| 3 | 6.5 | Intense |
| 4 | 6.5 | Intense |
| 5 | 6.5 | Intense |
| 6 | 6.5 | Intense |
| 7 | 6.6 | Intense |
| 8 | 6.6 | Intense |
| 9 | 6.6 | Intense |
| 10 | 6.6 | Intense |
| 11 | 6.6 | Intense |
| 12 | 6.6 | Intense |
| 13 | 6.6 | Intense |
| 14 | 6.6 | Intense |
| 15 | 6.6 | Intense |
| 16 | 6.6 | Intense |
| 17 | 6.6 | Intense |
| 18 | 6.6 | Intense |
| 19 | 6.6 | Intense |
| 20 | 6.6 | Intense |
| 21 | 6.5 | Intense |
| 22 | 6.5 | Intense |
| 23 | 6.5 | Intense |
| 24 | 6.5 | Intense |
| 25 | 6.5 | Intense |
| 26 | 6.5 | Intense |
| 27 | 6.5 | Intense |
| 28 | 6.5 | Intense |
| 29 | 6.5 | Intense |
| 30 | 6.4 | Intense |
Hazard calendar for Riachão
None of Riachão's seasonal hazards are active in September. 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.
Is September a good time to visit Riachão?
Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).
September is a weaker month for outdoor sightseeing in Riachão. The water and warmth also suit a beach or pool day.
What to pack for Riachão in September
From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In September, Riachão sees daytime highs around 35°C and nights near 23°C. Pack light clothes and sun protection.
UV index in Riachão in September
Clear-sky midday UV in September peaks around 12 (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.
| 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 |
Air quality in Riachão in September
Average fine-particle pollution (PM2.5) through the year — so you can see where September 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).
| 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 |
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).