Ha Long Bay weather in May
Temperature, sea and sunshine in May: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in May
Poor
Best time to visit: November – April
What is the weather like in Ha Long Bay in May?
In May, Ha Long Bay is hot: daytime highs average 30 °C, and even at night it stays warm at around 25 °C. The sea averages 26.9 °C – lovely and warm for swimming. Expect around 5 hours of sunshine a day. It rains often – on about 20 days, adding up to 220 mm. On about 14 days the thermometer climbs to 30 °C or more. The air is often humid and muggy. All in all, May is not an ideal month for a holiday in Ha Long Bay.
May compared
How the weather changes from April to June. Tap a month to open it.
More details for May
- Daylight
- 13 h 7 min05:14 – 18:21
- UV index
- 12 · extremeclear sky, noon (estimate)All months
- Muggy days
- 30 daysdew point 18 °C or moreAll months
- Wind
- 16 km/haverage daily peakAll months
- Cloud cover
- 74 %on averageAll months
- Hot days
- 14 days30 °C or moreAll months
- Time zone
- UTC+7Asia/Bangkok
How the score comes together
- Temperatureweight 50 %60 %
- Sunshineweight 20 %38 %
- Few rainy daysweight 30 %0 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Nature escape”.
What to pack in May
- Swimwear
- Sunscreen
- Sunglasses & sun hat
- Light, breathable clothes
- Water bottle – drink plenty
- Insect repellent
- Rain jacket or umbrella
Ha Long Bay in May: quick answers
Is Ha Long Bay hot in May?
Yes. In May, Ha Long Bay is hot: daytime highs average 30 °C and nights stay around 25 °C. On about 14 days the thermometer climbs to 30 °C or more.
Can you swim in Ha Long Bay in May?
Yes. In May the sea averages 26.9 °C – lovely and warm for swimming.
Does it rain much in Ha Long Bay in May?
It rains often – on about 20 days, adding up to 220 mm.
Ha Long Bay month by month
The whole year in Ha Long BayAll destinations: VietnamWhere to go in MaySea temperature in May
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences