According to the National Center for Hydro-Meteorological Forecasting, the cold air mass in the north is continuing to move south.
Around the night of September 21 and early morning of September 22, this cold air mass will affect the Northeast region, then affect most of the Northwest region and some places in the North Central region. The wind will change to the northeast at level 3 inland, and level 4-5 in coastal areas.
On September 22-23, the weather in the North and Thanh Hoa will turn cool, while some mountainous areas in the North will be cold. During this cold air mass, the lowest temperature in the North and Thanh Hoa will be from 20-23 degrees Celsius, while in mountainous areas, it will be below 19 degrees Celsius.
Thunderstorms may produce tornadoes, lightning, hail and strong winds.
The meteorological agency added that from the evening of September 21 to the night of September 23, in the midlands and deltas of the North, Hoa Binh, North Central and Central Central regions, there will be moderate rain, heavy rain, locally very heavy rain and thunderstorms with common rainfall of 50 - 150mm, locally over 200mm.
Thunderstorms accompanied by tornadoes, lightning, hail and strong winds can affect agricultural production, cause trees to fall, damage houses, traffic works and infrastructure.
Heavy rains can cause flooding in low-lying areas; flash floods in small rivers and streams, and landslides on steep slopes.
At sea, from early morning on September 22, the northeast wind in the Gulf of Tonkin gradually increased to level 6, sometimes level 7, gusting to level 8; rough seas; waves from 1.5 to 2.5m high.
Strong winds and large waves at sea are likely to affect boating and other activities.
