Short answer
Warm, increasingly humid and good for swimming. Showers become more frequent later in the month, and weekends get busy from mid-May.
Day high30 °C
Night low24 °C
Sea27.0 °C
Rainfall190 mm
Rainy days13
SwimmingVery good
Boat tripsVery good
HikingGood
CrowdsModerate
01Weather
Daytime highs reach about 30 °C and the humidity climbs. Rain becomes more frequent as the month goes on, typically in heavy afternoon or evening bursts rather than all day. Mornings are often the clearest time of day.
02On the water
The sea warms to around 27 °C, comfortable for long swims and Kayaking. Boat days are excellent, and late May brings the first chance of seeing the bioluminescent plankton on night trips in some areas.
03Who it suits
- Couples and friends who want warm water without peak crowds
- Climbers looking at deep water soloing once the water is warm
- Families before the school holidays begin
?Questions people ask
Is May a good month for Cat Ba?
Yes, one of the best for swimming and boats before the June to August peak.
Does it rain a lot in May?
More than in April, but usually in short heavy showers, leaving plenty of dry hours.