A cold air mass sweeping across Vietnam on 4 January 2026 will bring widespread low temperatures in the north, frost and the risk of freezing on high ground, while the south experiences sunny days but cool mornings. National meteorological services warn of rough seas and strong northeasterly winds across the East Sea and southern waters.
Vietnam weather 4 January 2026 warnings
Forecasters say the coldest conditions will affect Bắc Bộ and the northern mountain provinces. Minimum temperatures in lowland northern areas are forecast at 12–15°C, with mountain valleys from 9–12°C and some high-altitude spots dipping below 8°C. Agencies have advised residents in highland districts to prepare for băng giá and possible damage to sensitive crops.
In Thanh Hóa and Nghệ An light rain is expected in places with mist at dawn. The broader North Central coast through Quảng Trị and Thừa Thiên–Huế will see cooler conditions, with daytime highs between 16°C and 19°C in those stretches. From Hà Tĩnh to Đà Nẵng and eastwards through Quảng Ngãi to Gia Lai scattered showers are likely, and temperatures will remain on the cool side.
The southern half of the country sits on the southern fringe of the cold air mass. That keeps daytime weather largely dry and sunny with a cool feel at night and in the early morning. Forecasts for the Nam Bộ region indicate lows of 19–22°C and daytime temperatures reaching 30–33°C. Ho Chi Minh City should expect a low of 21–23°C and a high of 31–33°C.
On the water, the report highlights hazardous conditions. The northern East Sea, including the Hoàng Sa area, will see northeasterly winds at force 6 and rough seas with waves of 4–6 metres. The stretch from Khánh Hòa to Cà Mau and the western sectors of the southern East Sea, including areas west of Trường Sa, will see winds at force 6 and occasionally force 7 with gusts to force 8 or 9. Wave heights are expected at 4–6 metres and sea conditions will be very rough.
Between Quảng Ngãi and Đắk Lắk and across the mid-Biển Đông to the eastern sectors of the southern East Sea, winds will reach force 6 with gusts to force 7–8 and waves of 3–5 metres. Mariners are advised to avoid small craft voyages and to secure vessels. Authorities have urged fishing communities to remain in port until conditions ease.
Detailed city forecasts include Hà Nội, where skies will be mostly cloudy and cold with temperatures between 14°C and 20°C. The northwest and northeast regions will be cold with localised severe cold in highlands. Coastal central provinces will see scattered showers and milder daytime temperatures of 21–24°C. The central highlands will have cool nights and sunny days, with lows of 14–17°C and highs up to 29°C.
Officials recommend that residents in affected northern and highland areas protect vulnerable people, livestock and crops from the cold. Travellers should check road and weather updates before heading for highland routes, and all coastal users must heed maritime warnings until seas abate.
Outlook: the cold air mass is expected to remain influential over the northern regions for the next 24–48 hours, with gradual easing thereafter. Marine conditions will take longer to calm and should be monitored closely by seafarers and coastal communities.
Key Takeaways:
- Vietnam weather 4 January 2026: Northern provinces will see sharply colder temperatures with mountain frost and some areas below 8°C.
- Coastal and offshore waters will experience strong northeasterly winds, with waves of 3–6 metres and gale-force gusts in places.
- Central and southern regions remain largely dry and sunny by day, but nights and mornings will be cool to chilly.
