December · Brazil
Best time to visit Alter do Chão in December Weather, crowds & prices
Weather in Alter do Chão in December
Average temperature 29°C, 90 mm of rain, about 19 days with 6+ hours of sunshine and 70% humidity — based on the five most recent complete years of ERA5 data (2021–2025).
December score
8.2/10
Ranked #6 of 12 months
- Avg temp
- 29°C
- Rainfall
- 90 mm
- Humidity
- 70%
- Days with 6h+ sun
- 19
- Crowd Density
- Moderate Crowds
- Average Expenses
- $$ · Moderate Cost ($$)
December in Alter do Chão scores 8.2/10 for beach and coastal travel - an above-average month (#6 of 12). Expect around 29°C, 90 mm of rain, and roughly 19 days with 6+ hours of sunshine this month.
The 'Caribbean of the Amazon'—white-sand river islands and clear Tapajós water—peaks in the low-water months from August through December.
December in Alter do Chão — reliably good (6th best month)
December averages 29°C (85°F), so the practical pattern is early mornings, a long midday break, and evenings back outside.
Rainfall runs 90 mm, so plan one flexible day in three; you still get about 19 days with 6+ hours of sunshine and 12.1 hours of daylight.
It scores 8.2/10 here, 6th of 12 months, against 9.9/10 in the destination's best month.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a packable rain layer.
Figure on mid-season pricing, with crowds are moderate.
Flexible dates? September scores 1.7 points higher here — enough to change the trip.
Frequently asked
- What is the weather like in Alter do Chão in December?
- In December, Alter do Chão averages 29°C, 90 mm of rain, and about 19 days with 6+ hours of sunshine. Its climate-comfort score is 8.2/10.
- Is December a good time to visit Alter do Chão?
- December earns a 8.2/10 climate-comfort score. Use the year-round chart to weigh the weather against your budget and crowd preferences.
- How much does it rain in Alter do Chão in December?
- Expect about 90 mm of rain in December. Average humidity is 70% and there are about 19 days with 6+ hours of sunshine.
Curated in Alter do Chão
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Things to do in Alter do Chão
Alter do Chão, Brazil. Live activities and tours from GetYourGuide, matched to this destination.