The La Nina weather phenomenon that is developing in the Pacific region will not only drop temperatures but also cause more rain and storms in Asia, including Vietnam, said the World Meteorological Organisation (WMO) and the Vietnamese Ministry of Natural Resources and Environment.

The WMO said that La Nina is characterised by unusually cool ocean temperatures in the east Pacific and the weather is expected to get harsher on a much larger scale in the coming months.

In late 2008, La Nina was blamed for icy conditions that claimed dozens of lives across Europe and brought torrential rain to Indonesia , Malaysia and Australia.

In Vietnam, La Nina made the summer of 2008 much cooler than previous summers and Hanoi and neighbouring areas also record the heaviest downpours in 40 years in late October with an approximate rainfall of 1m./.