Vietnam's climate is remarkably varied for a country of its size, ranging from the sub-tropical winters of Hanoi in the north to the near-equatorial tropics of the Mekong Delta in the south. The country's distinctive S-shape stretches 1,650 kilometres from top to bottom along the South China Sea coast, and at any given time of year, three very different weather regions can be experiencing three very different climates.
Climate
Vietnam is one of the few Southeast Asian countries with a genuine "cool season" in its northern half. Hanoi, the capital, sits around 21° north of the equator — a latitude similar to southern Taiwan — and experiences real winters with overnight lows that can drop to 8–10°C in January. Humidity remains high even during the cool season, so the winters feel raw and damp rather than crisp.
The country is divided climatically into three regions: the north (Hanoi, Ha Long, Sapa), the central coast (Hue, Da Nang, Hoi An) and the south (Ho Chi Minh City, Mekong Delta). Each region has a different rainy season and a different optimal travel window, which is why timing a trip through all three regions is genuinely tricky — there is no single month that is good everywhere.
Vietnam sits on the western edge of the Pacific typhoon track and is regularly struck by tropical storms, especially along the central coast from August through November. On average Vietnam is hit by 6–10 named storms per year, and the strongest ones can be devastating for coastal communities and inland agriculture.
Seasons
Northern winter (December – February)
Hanoi and the north are cool, grey and often drizzly. Daytime highs are typically 15–20°C, nights can drop to 8–10°C in the city and approach 0°C in the mountains around Sapa (where frost and rare snow have been recorded). The famous "phùn" drizzle — a persistent fine mist — is characteristic of late winter and spring in the Red River Delta.
Spring (March – April)
Temperatures warm quickly through March and April. The north remains humid and often overcast in March before clearing in April. The central coast is in its dry season and offers the best weather of the year. The south is hot and dry — this is the tail end of the southern dry season and temperatures in Ho Chi Minh City regularly hit 35–37°C.
Summer (May – August)
Hot and humid across the entire country. Northern Vietnam enters its own rainy season in May with heavy afternoon thunderstorms. The central coast remains relatively dry until late August. The south is in the middle of its wet season with daily downpours. Typhoon season begins building in the South China Sea.
Autumn / typhoon season (September – November)
The most volatile time of year. September and October are peak typhoon months for the central coast, with Hue and Da Nang particularly exposed. Flooding in Hue is almost an annual event. Hanoi cools off and enters its best weather window in late October and November. The south continues its rainy season through October before drying out in November.
Extreme weather events
Central Vietnam is one of the most typhoon-prone areas in Southeast Asia. Typhoon Haiyan (2013), while most destructive in the Philippines, brought damaging winds and flooding to central Vietnam. Typhoon Damrey in 2017 killed over 100 people along the south-central coast. Flooding in Hue during the 1999 historic floods submerged the old imperial city for weeks. In the north, extreme cold snaps occasionally bring frost to the mountains and highland rice crops.
Regional variation
The north (Hanoi, Sapa, Ha Long Bay) has four seasons — a genuine winter, warm spring, hot summer and cool autumn. Sapa in the far north-west occasionally sees snow above 1,500 metres elevation.
Central Vietnam (Hue, Da Nang, Hoi An, Nha Trang) has a distinctive climate with a short dry season from January to August and a concentrated wet season from September to December. It is also the most typhoon-exposed part of the country.
The south (Ho Chi Minh City, Mekong Delta, Phu Quoc) is tropical year-round with no real "cool" season. It has a classic wet/dry monsoon split — May to November is wet, December to April is dry.
The Central Highlands (Da Lat, Buon Ma Thuot) sit at 1,000–1,500 metres elevation and are significantly cooler than the surrounding lowlands. Da Lat, known as Vietnam's "City of Eternal Spring", has daytime highs that rarely exceed 25°C.
Best time to visit
There is no single best time to see all of Vietnam. For a trip covering the whole country, March and April offer the best compromise: the north has warmed up, the central coast is dry, and the south is hot but manageable. For the north specifically, October and November are ideal. For the central coast, February to May. For the south, December to March. Avoid the central coast from September to November if you want to avoid typhoon disruption.
Climate facts
- Sapa, in the northwest mountains, is one of the few places in Southeast Asia where snow falls occasionally — usually once every few winters on the highest peaks.
- Ho Chi Minh City and Hanoi are so climatically different that a morning flight between them can feel like travelling between two continents — especially in January when HCMC is 32°C and Hanoi is 12°C.
- Da Lat, at 1,500 metres elevation, was chosen by the French colonial administration as a mountain retreat specifically because its climate resembles parts of France more than tropical Vietnam.
- Central Vietnam holds the record for the highest 24-hour rainfall in the country: over 900 mm fell on Hue during the 1999 floods.