December weather forecast
Cook Islands

December in the Cook Islands marks the official onset of the wet season, characterized by increased temperatures, high humidity, and substantial rainfall. Average temperatures during this month range from 23°C to 29°C, signifying the return of the tropical warmth that defines this time of year.

Rainfall in December is notably high. The southern islands, including Rarotonga and Aitutaki, experience rainfall exceeding 250mm, indicating the full swing of the wet season. The northern islands, such as Manihiki and Penrhyn, while generally receiving less rainfall, also see a significant increase in precipitation compared to the dry season.

December also marks the beginning of the South Pacific cyclone season. Although the Cook Islands do not frequently experience cyclones, it is vital to stay updated with local weather forecasts due to the increased possibility of such events.

When comparing December to November, both temperatures and rainfall levels increase, indicating the full onset of the wet season. Looking ahead to January, these weather conditions continue to intensify, with both temperature and precipitation further rising. Therefore, December represents the beginning of the wet and warm season in the Cook Islands, a time characterized by its tropical climate.

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• Roto - December »
  In Roto in December, during 26.6 rainfall days, 193mm of precipitation is typically accumulated. The months with the highest UV index in Roto are January through December, with an average maximum UV index of 7.
• Tauhunu - December »
  January through June, October through December, with an average sea temperature of 29°C, are months with the warmest seawater in Tauhunu, Cook Islands. The month with the longest days in Tauhunu is December, with an average of 12h and 42min of daylight.
• Mapumai - December »
  The months with the highest UV index in Mapumai are January through March, May, November and December, with an average maximum UV index of 7. In Mapumai, Cook Islands, in December, during 22.9 rainfall days, 153mm of precipitation is typically accumulated.
• Avarua District - December »
  The month with the longest days in Avarua District, Cook Islands, is December, with an average of 13h and 24min of daylight. In December, the tropical surroundings of Avarua District, Cook Islands are heightened by further increase in temperature and rainfall.
• Arutanga - December »
  In Arutanga in December, the average water temperature is 27°C. December in Arutanga sees a further increase in average rainfall, reverting to the wet weather patterns seen at the beginning of the year.
• Omoka Village - December »
  The month with the longest days in Omoka Village is December, with an average of 12h and 36min of daylight. Temperatures in Omoka Village reach their maximum during January, March through July, September through December, recording an average high-temperature of 31°C.
• Mangarei Village - December »
  The months with the highest UV index in Mangarei Village are January through March, May, November and December, with an average maximum UV index of 7. The month with the longest days in Mangarei Village is December, with an average of 13h and 18min of daylight.
• Oneroa Village - December »
  The months with the highest UV index in Oneroa Village are January through March, October through December, with an average maximum UV index of 12. The month with the longest days in Oneroa Village is December, with an average of 13h and 24min of daylight.
• Tautu - December »
  In Tautu, during December, the rain falls for 19 days and regularly aggregates up to 148mm of precipitation. The months with the highest UV index in Tautu are January through May, October through December, with an average maximum UV index of 7.
• Nukuao - December »
  November and December, with an average relative humidity of 79%, are most humid months in Nukuao, Cook Islands. The months with the highest humidity in Nukuao are November and December, with an average relative humidity of 79%.
• Ngatiarua - December »
  The months with the highest humidity in Ngatiarua are November and December, with an average relative humidity of 79%. Closing the year, December's weather in Ngatiarua substantially resembles conditions seen in November, with a slight increase in humidity and rainfall.
• Karanga Village - December »
  The months with the highest humidity in Karanga Village are November and December, with an average relative humidity of 79%. In Karanga Village, Cook Islands, during December, the rain falls for 22.9 days and regularly aggregates up to 153mm of precipitation.