BEIJING - Chinese marine forecasting authorities have issued a marine disaster alert as a weak La Nina weather pattern is likely to affect the country's sea areas this winter.

A weak pattern is forecast to form in the equatorial eastern central Pacific Ocean, according to a statement released Friday by the National Marine Environmental Forecasting Center (NMEFC).

Cold air processes this winter are more active, and more wind and waves have been forecast in China's eastern and southern sea areas due to La Nina. Ice in China's northern sea area will gradually form in December.

The center advised preparations for storm surges, waves and sea ice.

Yi Xiaolei, deputy director of the NMEFC, said that the center will closely observe the evolution of the ocean and atmosphere in the equatorial Pacific and release alerts as appropriate.

La Nina, the opposite of El Nino, is an oceanic atmospheric phenomenon characterized by low sea temperatures across the equatorial eastern central Pacific. It often occurs after a strong El Nino event.