As per the National Centre for Hydro-Meteorological Forecasting, a cold air mass moving southward is forecast to begin affecting northern Vietnam from Thursday (01 January 2026), before extending into the North Central, Northwest, Central, and parts of the South Central regions over the following 24 to 48 hours.

• From the night of Wednesday (31 December) into Thursday (01 January 2026), scattered rainfall, showers, and isolated thunderstorms are anticipated across the North, including Thanh Hoa and Nghe An. Northeasterly winds are expected to strengthen, particularly along coastal areas.
• From Thursday (01 January 2026), temperatures across the Northern and North Central regions are forecast to decline markedly. Lowland areas in the North may record temperatures between 11 and 14 degrees Celsius, while mountainous and midland areas could see 8 to 11 degrees Celsius, with higher elevations falling below 7 degrees Celsius.
• In the Hanoi area, scattered rainfall is likely from the night of Wednesday (31 December) into Thursday (01 January 2026), followed by colder conditions from the afternoon of Thursday (01 January 2026), with minimum temperatures ranging between 12 and 14 degrees Celsius.