According to the National Center for Hydro-Meteorological Forecasting, on the morning of May 2nd, in the North, there is a cold air mass compressing and pushing a low pressure trough with its axis at about 25–27 degrees North latitude moving southward. In the North, there are showers and thunderstorms in some places, especially in the Northwest region, there are scattered showers and thunderstorms, locally heavy rain, common temperature 21–24 degrees C, mountainous areas in some places below 20 degrees C.
It is forecasted that around the afternoon and evening of May 3rd, this cold air mass will affect the Northeast region, then affect the North Central region, some places in the Northwest region and the Central Central region. On land, the wind will turn Northeast at level 2-3, coastal areas at level 3-4.
In the Northeast and North Central regions from the afternoon and night of May 3rd, the weather will turn cool. The lowest temperature in this cold air wave in the Northeast region is commonly from 20–23 degrees C, mountainous areas in some places below 20 degrees C; in the North Central region, it is commonly 21–24 degrees C.
In Hanoi area, in the afternoon and night of May 3rd, there will be rain, moderate rain and scattered thunderstorms, locally heavy to very heavy rain; the weather will turn cool. The lowest common temperature is 21–23 degrees C.
On May 3rd day and night, the Northern region and Thanh Hoa will have rain, moderate rain and scattered thunderstorms with rainfall of 20–40mm, locally heavy to very heavy rain over 90mm.
From the afternoon of May 3rd to the morning of May 4th, the area from Nghe An to Hue City will have scattered showers and thunderstorms with rainfall of 10–30mm, locally heavy rain over 50mm. In thunderstorms, there is a high possibility of tornadoes, lightning, hail and strong gusts of wind.
At sea, from the evening and night of May 3rd, in the Northern Gulf of Tonkin, the wind will turn Northeast at level 5, sometimes level 6, gusting to level 7, waves 1.5–2.5m high, rough seas.
From near dawn on May 4, the northeastern sea area of the Northern East Sea has strong Northeast wind at level 6, gusts at level 7–8, waves 2.0–3.0m high, rough seas.
People and tourists should be wary of thunderstorms accompanied by tornadoes, lightning, hail and strong gusts of wind. Localized heavy rain is at risk of flash floods on small rivers and streams, landslides in mountainous areas and flooding in low-lying areas.
