The National Centre for Hydro-meteorological Forecasting said the cold air mass is moving south and is forecast to reach the northeastern region on the morning of January 31, before expanding to the Red River Delta and the northwestern region.
From the night of January 30 through January 31, the northeastern region and the north central region are expected to see light, scattered rain.
From the afternoon of January 31, the northeastern region and the north central region will turn cold, with some mountainous areas experiencing severe cold. The lowest temperatures are forecast at 12 to 15 degrees Celsius, falling to 9 to 12 degrees Celsius in northeastern mountainous areas, and below 8 degrees Celsius in some high mountain locations.
In Hanoi, light and scattered rain is forecast on the night of January 30 and during the day on January 31. From the afternoon of January 31, the weather will turn cold, with the lowest temperatures ranging from 13 to 15 degrees Celsius.
From February 1 to the morning of February 4, areas from Quang Tri to Danang and the eastern parts of Quang Ngai to Gia Lai are expected to see scattered rain and showers, with thunderstorms in some places. During thunderstorms, whirlwinds, lightning, hail and strong gusts of wind may occur.
Due to the influence of the cold air mass on January 31, the Gulf of Tonkin will see strong northeasterly winds at level 5, occasionally reaching level 6, with gusts at levels 7 to 8, causing rough seas with wave heights of 1 to 2 metres.
In the northeastern waters of the northern East Sea, northeasterly winds are forecast at level 6, with gusts at levels 7 to 8. Sea conditions will be rough, with waves reaching 2 to 4 metres.