8.7· 3 reviews
Tapajós National Forest Tour
Venture into the Brazilian rainforest and discover the animals that live there on our 1 or 2-day Tapajós National Forest Tour.
2 days
from US$ 77
Short answer
In September, Alter do Chão averages highs of 32 °C (90 °F) and lows of 22 °C (72 °F), with about 58 mm of rain spread over roughly 7 days. September has moderate rainfall, usually in quick showers that do not spoil the whole day. Crowds tend to be moderate this month.
Climate · INMET (updated 2026)
Temperature
32 / 22 °C
high / low
Rain
58 mm
7 days
Daylight
12h06
sunset at 18:36
Crowds
Moderate
1 public holiday
What to expect in Alter do Chão in September
Editor's tip
September is spring in Alter do Chão. In Brazil the seasons are the reverse of those in the Northern Hemisphere. Highs reach 32 °C (90 °F): the heat calls for early starts, sunscreen, and spending the middle of the day in the shade or in the water. Crowds sit somewhere in the middle, with peaks on public holidays. Outside those dates, you can enjoy the place at an easy pace and spend less. Rain, when it comes, is usually brief and does not spoil the day. If the dates line up, it is worth fitting Sairé Festival (Festa do Sairé, or Çairé) into your itinerary: it is what livens up the destination at that time of year.
Myllena Vieira · Editor at VisiteCrowds
Crowd level: moderate
Moderate crowds, with peaks on public holidays. Outside those dates, you can enjoy the place at a calmer pace.
Prices
Rates: moderate · ~R$ 544
Moderate prices outside public holidays, which push rates and crowds up. The average nightly rate for lodging in Alter do Chão is around R$ 544 (Brazilian reais), depending on the date.
Tours and tickets
Things to do in Alter do Chão in September
Where to stay
Hotels in Alter do Chão
In September, demand in Alter do Chão is moderate: most hotels have room, but public holidays fill them up. Compare rates and book a few weeks ahead.
Rates change with the dates: confirm the price on Booking.com.
What happens in September
Sairé Festival (Festa do Sairé, or Çairé)
A traditional festival that combines religious ritual with the festival of the botos (river dolphins), featuring the contest between Boto Tucuxi and Boto Cor de Rosa, in the third week of September.
Public holidays in September: Independence Day (07/09). Expect more people and higher prices around these dates.
What to pack in September
Light clothing and a cap · highs of 32 °C (90 °F) Sunscreen and sunglasses · strong sun on the tours Quick-dry clothing · humidity of 82% Comfortable walking shoes · you will be on foot much of the day
Looking for better weather?
Where the weather is good in September
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