Climate averages 1991–2020
Cacoal weather
in September.
A hot, wet month: the 2nd warmest and the 5th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a hot month in Cacoal: daytime highs average 33.3°C and nights cool to about 23.0°C. By daytime temperature it is the 2nd warmest of the 12 months.
Expect about 90 mm of rain on roughly 14 days, which makes September a wet month (the 5th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 02 min on an average September day.
The nearest other city in this atlas is Ji Paraná (83 km away). In September its highs average 33.3°C, about as warm as Cacoal, with 80 mm of rain.
Among the 448 cities listed in Brazil, Cacoal ranks joint 40th of 448 for the warmest September highs and joint 326th of 448 for the driest September (rainfall, lowest first). The mean September high of those 448 cities is 27.5°C; Cacoal is 5.8°C warmer than that mean.
From September to October, average highs fall by 1.3°C to 32.0°C, and monthly rainfall rises from 90 mm to 156 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Cacoal climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 29.1°C22.7°C | 22.7°C | 308 | 29.3 | 12.713 h |
| February | 28.9°C22.6°C | 22.6°C | 299 | 26.6 | 12.512 h |
| March | 29.2°C22.6°C | 22.6°C | 270 | 28.2 | 12.212 h |
| April | 29.3°C22.4°C | 22.4°C | 151 | 22.3 | 11.912 h |
| May | 29.3°C21.6°C | 21.6°C | 77 | 13.4 | 11.612 h |
| June | 30.7°C20.5°C | 20.5°C | 17 | 3.5 | 11.511 h |
| July | 32.2°C20.3°C | 20.3°C | 11 | 2.1 | 11.512 h |
| August | 33.7°C21.5°C | 21.5°C | 26 | 4.7 | 11.712 h |
| September, selected | 33.3°C23.0°C | 23.0°C | 90 | 14.1 | 12.012 h |
| October | 32.0°C23.2°C | 23.2°C | 156 | 21.7 | 12.312 h |
| November | 30.3°C22.9°C | 22.9°C | 239 | 24.9 | 12.613 h |
| December | 29.4°C22.8°C | 22.8°C | 284 | 27.9 | 12.813 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Ji Paraná in SeptemberBrazil · 83 kmHigh 33.3°C · Low 23.2°C · 80 mm rain
- Vilhena in SeptemberBrazil · 202 kmHigh 30.8°C · Low 20.9°C · 84 mm rain
- Ariquemes in SeptemberBrazil · 243 kmHigh 33.1°C · Low 23.3°C · 86 mm rain
- Porto Velho in SeptemberBrazil · 401 kmHigh 32.6°C · Low 23.8°C · 103 mm rain
- Riberalta in SeptemberBolivia · 505 kmHigh 32.2°C · Low 23.1°C · 84 mm rain
- Trinidad in SeptemberBolivia · 531 kmHigh 31.2°C · Low 22.2°C · 106 mm rain
- Tangará da Serra in SeptemberBrazil · 556 kmHigh 32.3°C · Low 21.2°C · 56 mm rain
- Lucas do Rio Verde in SeptemberBrazil · 628 kmHigh 33.3°C · Low 22.4°C · 50 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Cacoal) is explained once on the Cacoal year overview and on the Sources, method and limits page.