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 (73.4°F) to 29°C (84.2°F), 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 (9.84"), 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 (7.6") of precipitation is typically accumulated. The months with the highest UV index in Roto, Cook Islands, 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 (84.2°F), are months with the warmest seawater in Tauhunu, Cook Islands. January through December, with an average maximum UV index of 7, are months with the lowest UV index in Tauhunu, Cook Islands.
• Mapumai - December »
  The month with the longest days in Mapumai, Cook Islands, is December, with an average of 13h and 18min of daylight. In Mapumai in December, it is raining for 22.9 days, with typically 153mm (6.02") of accumulated precipitation.
• Avarua District - December »
  In Avarua District during December, the rain falls for 11 days and regularly aggregates up to 229mm (9.02") of precipitation. On the first day of December in Avarua District sunrise is at 05:48 and sunset at 19:08.
• Arutanga - December »
  December has the longest days of the year in Arutanga, with an average of 13h and 12min of daylight. 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 temperature in Omoka Village hits its peak in January, March through July, September through December, recording an average high-temperature of 31°C (87.8°F). The months with the warmest seawater in Omoka Village are January through June, October through December, with an average sea temperature of 29°C (84.2°F).
• Mangarei Village - December »
  The months with the highest humidity in Mangarei Village are November and December, with an average relative humidity of 79%. 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.
• Oneroa Village - December »
  With an average of 13h and 24min of daylight, December has the longest days of the year in Oneroa Village, Cook Islands. January through March, October through December, with an average maximum UV index of 12, are months with the highest UV index in Oneroa Village, Cook Islands.
• Tautu - December »
  The months with the highest UV index in Tautu are January through May, October through December, with an average maximum UV index of 7. In Tautu, in December, during 19 rainfall days, 148mm (5.83") of precipitation is typically accumulated.
• Nukuao - December »
  The months with the highest UV index in Nukuao are January through March, May, November and December, with an average maximum UV index of 7. December has the longest days of the year in Nukuao with an average of 13h and 18min of daylight.
• Ngatiarua - December »
  January through March, May, November and December, with an average maximum UV index of 7, are months with the highest UV index in Ngatiarua, Cook Islands. With an average of 13h and 18min of daylight, December has the longest days of the year in Ngatiarua, Cook Islands.
• Karanga Village - December »
  In Karanga Village during December, the rain falls for 22.9 days and regularly aggregates up to 153mm (6.02") of precipitation. November and December, with an average relative humidity of 79%, are most humid months in Karanga Village.