A cloudy with showers outlook for Christmas Day in Tonga is forecasted by the National Weather Forecast Centre at Fua'amotu.

'Ofa Fa'anunu, the Director of Meteorology announced on December 22 that an active trough that lies over Tonga was expected to bring cloudy conditions and showers to the Tonga group over the next five to six days.

He said the forecast for on December 25 is for moderate to North to Northeast winds throughout the islands turning light and changeable at times, particularly in Tongatapu and 'Eua.

It would be mostly overcast with showers heavy at times in Vava'u, Ha'apai, Tongatapu and 'Eua and elsewhere would have cloudy periods and brief showers, he forecast.

Rain

He said the weather outlook for the next few days in Tonga is caused by the current climate change situation in Tonga due to a weak to moderate La Nina condition that currently exists in the Tropical Pacific, which he expected to persist through the remainder of 2011 and possibly into early 2012.

One of the effects of the La Nina weather condition is rain, and Tonga should expect higher than average rainfall during the summer months of November to April, and expect lower than average occurrence of the tropical cyclone season, he said.

He said the tropical cyclone outlook for Tonga is moderate to high with a 71 percent likelihood of being affected by a tropical cyclone in the 2011-12 cyclone season.

The tropical cyclone outlook for the South Pacific is that five to eight cyclones would affect the South Pacific region in the 2011-12 season, with four to five of these expected to reach category 3 strength, with one or two reaching category 4 or 5, he said.