Cold wave grips northern Vietnam as temperatures plunge to 3 C, health risks warned

On the morning of Jan. 6, the second day of intensified cold air sweeping the region, Mau Son peak in Lang Son Province recorded the lowest temperature at just 3 degress. Other high-altitude locations such as Sa Pa, Dong Van and Tam Dao saw temperatures drop to around 6 degress, while many mountainous districts reported lows of 7–9 degrees.

In Hanoi and surrounding lowland areas, temperatures fell to between 12 and 15 degrees, down 1–2 degrees from the previous day. Ba Vi and Son Tay recorded 12 degrees, while Ha Dong and Hoai Duc were at 13 degrees, and Lang station measured 14 degrees.

Central Vietnam is also feeling the chill, with temperatures ranging from 14 to 20 degrees, rising gradually from north to south. Many areas in Thanh Hoa Province recorded lows of 14 degrees, while Khe Sanh in Quang Tri and Hue saw temperatures drop to around 17 degrees.

Frost was observed forming thickly on Phia Oac peak in Cao Bang Province at midday on Jan. 6, where temperatures fell to minus 1 degree. Local residents described strong winds and biting cold, with ice covering large stretches of the mountaintop.

Thick ice coats tree branches in Cao Bang, northern Vietnam on Jan. 6, 2026. Photo by Dinh Hoi

The National Center for Hydro-Meteorological Forecasting said severe cold conditions are expected to persist across northern Vietnam. Minimum temperatures in the Red River Delta are forecast at 9–12 degrees, 6–9 degrees in mountainous areas, and below 5 degrees in high mountain regions. From Thanh Hoa to Nghe An, lows are expected to remain between 9 and 12 degrees.

The cold air mass is also bringing strong northeast winds and rough seas. In the Gulf of Tonkin and large parts of the East Sea, waves are forecast at 3–6 meters in some areas, posing risks to maritime activities.

Meteorological authorities warned that prolonged severe cold could affect public health, particularly among the elderly and children. Frost and freezing conditions may reduce immunity, increase the risk of disease outbreaks, and cause damage to livestock, crops and agricultural production.

Localized heavy rain may also lead to flooding in low-lying areas, flash floods in small rivers and streams, and landslides on steep slopes, especially during short periods of intense rainfall.