According to the National Centre for Hydro-Meteorological Forecasting, hot conditions in the southeastern region are likely to strengthen and spread to the Central Highlands and the Mekong Delta from April, before easing and gradually narrowing by late May and June.
Heat may also develop in north-western Vietnam and western areas from Thanh Hoa to Hue from around April, expanding across much of the north and central regions from late May, with intensity increasing in the following months.
Nguyen Duc Hoa, deputy head of the centre’s Climate Forecasting Division, said seasonal transition rains could occur in April in the north-west, north-central region, Central Highlands and southern Vietnam.
The rainy season in northern and southern Vietnam is expected to begin around mid-May, broadly in line with long-term averages, with moderate to heavy rainfall possible in several regions during May and June.
Storm and tropical depression activity over the East Sea this year is expected to remain near the long-term average. During April-June, around 1.8 systems typically form over the sea, with about 0.3 making landfall in Vietnam.
During the peak storm season from July to September, an average of about 6.5 storms form over the East Sea each year, with around 2.9 making landfall.
Cold air activity is expected to weaken gradually, while nationwide average temperatures will remain close to long-term norms, although northern Vietnam and the provinces from Thanh Hoa to Nghe An may see temperatures about 0.5-1 degree Celsius above average in April.
Total rainfall between April and June is forecast to remain broadly in line with long-term averages, though northern Vietnam and the provinces from Thanh Hoa to Hue may record totals about 5-10 per cent higher than normal in June.
Across the country, thunderstorms, lightning, hail and strong winds may occur, particularly during the seasonal transition in April and May.
Forecasters also warned that the southwest monsoon, storms and tropical depressions could bring strong winds and high waves affecting activities in the East Sea.