Vietnam in September
Compare the regions before choosing your route. These are long-term climate references; actual weather can differ.
Northern mountains
Transition monthRain remains possible as summer gradually gives way to the drier autumn.
Son La · 1991–2020. Figures are for Son La at 675 m, not Sa Pa at around 1,500 m. Higher areas are considerably colder; use this station only to illustrate regional seasonal patterns.
Annual table & sources ↗Northern lowlands & bays
Transition monthStill warm with showers; autumn does not begin everywhere on a fixed date.
Hanoi · 1991–2020. Hanoi represents the northern lowlands. Ha Long Bay has its own coastal and marine conditions; these figures are not boating advice.
Annual table & sources ↗Huế & north-central coast
Wet coastal monthThe wet coastal period develops. Check local warnings before outdoor excursions.
Hue · 1991–2020.
Annual table & sources ↗Đà Nẵng & Hội An
Wet coastal monthRainfall rises sharply. Keep beach days and outdoor excursions movable.
Da Nang · 1991–2020. Da Nang is the coastal reference, not a station in central Hoi An. Local rainfall and flooding can differ.
Annual table & sources ↗South-central coast
Transition monthA transition to wetter coastal months. Avoid relying on one fixed day for boat activities.
Nha Trang · 1991–2020.
Annual table & sources ↗Central highlands
Wetter seasonThe wettest month in this historical series. Assess walking routes using current conditions.
Da Lat · 1964–1998. Historical reference series from a JICA report (1964–1998). This is an older period than the other tables; do not compare the figures as same-period climate normals.
Annual table & sources ↗Southern mainland & Mekong Delta
Wetter seasonThe wettest month in this series. Allow for rain and possible local surface flooding.
Ho Chi Minh City · 1991–2020. City reference; rainfall can differ elsewhere in the Mekong Delta. Rain days mean at least 0.1 mm, not a full day of rain.
Annual table & sources ↗Phú Quốc & southwestern islands
Wetter seasonThe wettest month in this island series. Check forecasts and transport updates carefully.
Phu Quoc · 1991–2020. Do not apply this island series to Con Dao or all southern beaches. Wind, waves and local advice determine whether boating and swimming are suitable.
Annual table & sources ↗