The National Center for Hydro-Meteorological Forecasting has forecast cold air developments in the next 24 to 48 hours.
During the day and night of September 22, cold air continues to affect other places in the Northeast, then affects some places in the Northwest and North Central regions. Northeast wind inland level 2-3, coastal areas level 4-5.
During the day and night of September 22, the Northern Midlands and Delta, Hoa Binh will have moderate rain, heavy rain, locally very heavy rain and thunderstorms with common rainfall of 30 - 50mm, locally over 100mm.
On September 22-23, the weather in the North and Thanh Hoa will be cool, while in some mountainous areas in the North it will be cold. During this cold spell, the lowest temperature in the North and Thanh Hoa will be between 20-23 degrees Celsius, and in some mountainous areas below 19 degrees Celsius.
In Hanoi area, on September 22-23, the weather will be cool with the lowest temperature commonly ranging from 21-23 degrees Celsius.
From the morning of September 22 to September 23, the North Central region will have moderate to heavy rain, locally very heavy rain with rainfall from 40 - 90mm, locally over 150mm.
From the evening of September 22 to the night of September 23, from Quang Binh to Thua Thien Hue, there will be moderate rain, heavy rain, and locally very heavy rain with common rainfall from 40 - 90mm, in some places over 150mm; in Thua Thien Hue alone, 30 - 60mm, locally over 120mm.
Thunderstorms may produce tornadoes, lightning, hail and strong winds.
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 the morning of 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 2-3m high.
Strong winds and large waves at sea are likely to affect boating and other activities.
