December weather forecast
Brazil

December brings the onset of summer in Brazil, with temperatures in the northern regions and the Amazon Basin hitting their peak. Daytime temperatures frequently reach over 30°C (86°F), making for hot and humid conditions. Evenings provide a slight respite with marginally cooler temperatures, although the overall warmth is still palpable.

Coastal cities like Rio de Janeiro experience a further increase in temperatures, with the average ranging from 22.8°C (73°F) to 27.2°C (81°F). As the north-central coast of Brazil enters the peak of its sea temperatures, marine activities flourish, and coastal tourism thrives.

In the south, the approach of summer is more pronounced. Regions south of the Tropic of Capricorn undergo a substantial rise in temperatures, indicating the definitive onset of summer. The highlands and mountains, now devoid of winter's frost and snow, exhibit a warm climate conducive to outdoor activities.

Rainfall in December is characteristic of the peak wet season. The Amazon region experiences some of its highest annual rainfall totals, while the northeastern regions continue to see substantial precipitation. Rainfall across Brazil reaches its zenith in December, contributing significantly to the annual rainfall totals. As such, December is the beginning of the rainiest quarter of the year in Brazil, setting the stage for lush landscapes and thriving flora and fauna.

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• São Paulo - December »
  January, March, April and December, with an average relative humidity of 80%, are most humid months in São Paulo. In São Paulo in December, it is raining for 14 days, with typically 201mm (7.91") of accumulated precipitation.
• Rio de Janeiro - December »
  In Rio de Janeiro, in December, during 21.9 rainfall days, 98mm (3.86") of precipitation is typically accumulated. In Rio de Janeiro, in December, it is raining for 21.9 days, with typically 98mm (3.86") of accumulated precipitation.
• Brasília - December »
  November and December, with an average of 7.5h of sunshine, are months with the least sunshine in Brasília. December has the longest days of the year in Brasília, with an average of 13h and 6min of daylight.
• Salvador - December »
  January through March, September through December, with an average maximum UV index of 12, are months with the highest UV index in Salvador, Brazil. January through March, September through December, with an average maximum UV index of 12, are months with the highest UV index in Salvador, Brazil.
• Fortaleza - December »
  In Fortaleza during December, the rain falls for 6 days and regularly aggregates up to 44mm (1.73") of precipitation. The month with the longest days in Fortaleza is December, with an average of 12h and 18min of daylight.
• Belo Horizonte - December »
  The month with the most rainfall in Belo Horizonte is December, when the rain falls for 20 days and typically aggregates up to 319mm (12.56") of precipitation. The month with the most rainfall in Belo Horizonte is December, when the rain falls for 20 days and typically aggregates up to 319mm (12.56") of precipitation.
• Manaus - December »
  December has the longest days of the year in Manaus, with an average of 12h and 18min of daylight. January through May, August through December, with an average maximum UV index of 12, are months with the highest UV index in Manaus, Brazil.
• Curitiba - December »
  January through March, November and December, with an average maximum UV index of 12, are months with the highest UV index in Curitiba, Brazil. On the last day of December, in Curitiba sunrise is at 05:29 and sunset at 19:10 -03.
• Recife - December »
  December has the longest days of the year in Recife with an average of 12h and 36min of daylight. With an average of 12h and 36min of daylight, December has the longest days of the year in Recife.
• Porto Alegre - December »
  December is the least humid month in Porto Alegre, with an average relative humidity of 71%. December showcases the height of summer in Porto Alegre with warm weather, a high temperature nearing 29.8°C (85.6°F), and substantial rainfall of 60mm (2.36").
• Goiânia - December »
  The month with the most rainfall in Goiânia is December, when the rain falls for 19 days and typically aggregates up to 268mm (10.55") of precipitation. February and December, with an average relative humidity of 76%, are most humid months in Goiânia.
• Guarulhos - December »
  The month with the longest days in Guarulhos is December, with an average of 13h and 36min of daylight. December in Guarulhos culminates in the height of summer, with the year's highest temperature and rainfall parameters coming into play.