People in HCM City travel in heavy rain earlier this month. — VNA/VNS Photo Hồng Giang

HCM CITY — The rainy season will begin two or three weeks earlier than usual in the south this year because of the La Nina phenomenon, the Southern Hydro-Meteorological Station has forecast.

Lê Đình Quyết, its deputy head, said the rains usually start between May 10 and 15.    

The US National Oceanic and Atmospheric Administration defines La Nina as cooler than normal sea-surface temperatures in the central and eastern tropical Pacific Ocean impacting global weather patterns.

It occurs every three to four years and can persist for as long as two years. 

The station said heavy rains would occur in the afternoons and from now until June.

In August, when La Nina’s influence will reduce, the weather will be back to a neutral state, with strong convection clouds causing thunderstorms and winds.

La Nina returns to Việt Nam after a decade, but its influence has not been serious yet, according to hydro-meteorologist Lê Thị Xuân Lan. 

However, it is unpredictable so the country should take preventive measures against natural disasters.

The earlier arrival of rains will help southern provinces and cities have “comfortable” weather during summer this year.

According to experts, because of La Nina, the rainy season will also be shorter, and rainfall will be lower than normal.

Lan warned that southern provinces and cities should start storing water.

There has been heavy rain in many parts of HCM City, causing streets to flood and trees to fall, injuring several people, damaging cars and motorbikes.

Nhiêu Lộc canal was polluted with garbage after the heavy rains, causing fish to die. — VNS