In recent years, the weather in Vietnam has become hotter during summer and colder during winter.

This has led the Hydrometeorological Forecast Centre to warn ofunusual weather patterns as the changes were quicker and morecomplicated than in the past.

An official from the centre has asked relevant agencies to regularly adjust plans to cope with these developments.

The official said the unusual changes had made weather forecasting more difficult.

Deputy director of the centre, Le Thanh Hai, said the appearance ofsnow in hills in the northern provinces of Lao Cai, Ha Giang and CaoBang last week, for example, was outside meteorological predictions.

"The cold spell had been forecast," he said, "but we were completelysurprised when the temperature dropped to zero degrees Celsius and snowfell."

Snowfalls normally occurred from December to February, he said. This was the first time snow appeared in March.

Hai stressed that rising sea levels and hotter weather in the next 20to 50 years were not the only predicted effects of climate change.

He said people should also be aware that weather patterns had become more severe.

"The planning of socio-economic development and residential areasshould be made in harmony with these climate changes," Hai added.

"People should prepare to cope with any changes of climate," he said.

Hai also warned the public to be aware of the ongoing effects of theLa Nina phenomenon which could bring extra rain, whirlwinds andfloods./.