Weather in Belém in December

A hard month. December asks something of you. Go in knowing what. You should expect rain on 25 days of the month, which is more days wet than dry.

Belém barely has seasons. December scores 45 out of 100 against a best of 49 in February — a gap small enough that the month you choose matters far less here than the week you choose.

Rain on 25 of the month's 31 days, 6 of them heavy. At that frequency a wet-weather backup is not a contingency, it is the itinerary — book the indoor things first and treat the clear days as the bonus. Pack for 31.4 °C days and 24.8 °C nights; the spread matters more here than any single number.

What the averages hide

Averages flatten a month, and this one hides a few things: 23 days top 30 °C, making the heat continuous rather than occasional. Across the twenty years measured, the hottest December day reached 36.4 °C and the coldest night fell to 21.2 °C, and the wettest single day dropped 52 mm — roughly 28% of the month's rain in one day.

December is moderately variable: 87 mm in the driest year against 368 mm in the wettest, around an average of 188 mm. Roughly two Decembers in three land near that average, and the third does something else entirely.

Wind is light at 2.9 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 79%, high enough to notice on the warm days without dominating them.

How December sits in the year

The month is on the way down: 1.9 °C cooler than November, with January dropping another 2.4 °C. The first week and the last are not the same trip. Rain is the thing that moves: January brings 5 days more of it, so the earlier half of a flexible trip is the safer half.

Daylight in December

Belém sits close enough to the equator that daylight barely moves all year — 12.2 hours in December, against a range of just 0.2 hours across the whole calendar. Sunrise and sunset land at roughly the same time whenever you come.

An inland climate

Despite being inland, the year stays fairly even: 9.7 °C between the year's warmest afternoons and coldest nights.

How busy it gets

Busy. Popular without being frantic; book the things you care about, improvise the rest.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

December in Belém versus nearby

If Belém is one option among several, the nearby comparison is worth making. Fortaleza is a better bet in December — within a degree on temperature, 19 days less rain. Manaus is close enough to be a coin toss — within a degree on temperature, the same number of rain days.

So: December is effectively as good as it gets here — 4 points behind February, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Belém

See all twelve months in Belém, or where else to go in December.