According to the National Center for Hydro-Meteorological Forecasting, the cold air mass has now approached the northern mountainous region.
At noon and afternoon on December 11, cold air will affect the Northeast, then affect the Northwest, North Central and some places in the Central Central.
The weather in the North is getting colder, with some mountainous areas experiencing severe cold. The lowest temperature is around 14 - 17 degrees Celsius, in mountainous areas 11 - 14 degrees Celsius, and in high mountainous areas, some places are below 10 degrees Celsius. The average temperature is around 19 - 21 degrees Celsius; in mountainous areas 15 - 18 degrees Celsius, some places are below 14 degrees Celsius.
Hanoi area sometimes has light rain; the weather turns cold. The lowest temperature in this cold air mass is commonly 15 - 17 degrees Celsius.
Due to the influence of cold air combined with high-altitude easterly wind disturbances, from December 11 to about December 15, the Central and South Central regions will have moderate rain, heavy rain and thunderstorms, locally very heavy rain; the North Central region will have rain and showers.
Thunderstorms may cause tornadoes, lightning and strong gusts of wind. Heavy rain may cause flooding in low-lying areas; flash floods in small rivers and streams; and landslides on steep slopes.
During the day and night of December 12, the Northern region will experience deeper cold and continue to cool down. The lowest temperature will be around 14 - 17 degrees Celsius, in mountainous areas 11 - 14 degrees Celsius, in high mountainous areas some places will be below 10 degrees Celsius. The average temperature will be around 17 - 19 degrees Celsius; in mountainous areas 15 - 17 degrees Celsius, in some places below 13 degrees Celsius.
The North Central region will turn cold with the lowest temperature around 16 - 19 degrees Celsius. The average temperature is around 18 - 20 degrees Celsius.
From the night of December 12, cold air continues to strengthen and affect the Central Central region and some places in the South Central region. The wind changes to the northeast, strong level 3 inland, level 3-4 in coastal areas.
