HÀ NỘI — The El Nino phenomenon is highly likely to occur late this year, causing unpredictable storms during the second half of the rainy season in the autumn months, the National Centre for Hydro-Meteorological Forecasting said.

Some 13-15 storms and tropical depressions will occur during the rainy season, some three to four will directly affect the central provinces’ mainland, said Hoàng Đức Cường, director of the centre.

The rainy season will start late and be short in the northern region, he said. Rainfall in this area will be 10-30 per cent less than previous annual averages in May, September and October.

Rainfall in the central region will be 15-30 per cent less than previous years’ average in September and October.

The rainy season will also start late and in the Central Highlands and the southern region. Rainfall will be 30 per cent higher than previous years’ average from May to August, but 30 per cent less than average in October.

The average temperature will be higher than previous years from May to October in the north, but will not last long and not cause harsh summer heat.  

Thunderstorms, cyclones and hail are likely during the transition period between seasons (April-May) in the midlands, mountainous northern regions, north central region, Central Highlands, and southern region.

Floods and landslides are predicted to occur more frequently than last year in the northern region, and in upstream major rivers and minor streams in the central region and Central Highlands.

The stormy season will start later than previous years in the northern region, with flood peaks lower than average, reaching alarm level 2 (affecting agricultural production and livelihood of residents in low areas) on upstream the Hồng, Hoàng Long and Thái Bình Rivers, and level 3 (causing serious flooding that threatens to destroy infrastructure and livelihood of residents) in minor streams and rivers in mountainous areas.  

The season will start earlier than previous years in the central region, Central Highlands, and the Mekong River area. Flood peak is predicted to reach levels 2 and 3 on rivers from Quảng Bình to Bình Thuận central provinces and in the Central Highlands.

Flood peak in upstream Cửu Long River is also predicted to reach levels 2 and 3. Floods are predicted to progress faster than average in this area due to heavy rainfall upstream.

Big waves are predicted in May in the north of the East Sea due to early storms, and in southwestern waters due to early monsoons.

High tides will occur in the coastal southern areas in October, with average tidal amplitude levels. — VNS