Short answer
A good month for boat trips and hiking, with fewer crowds than summer. The sea warms but is still cool; the 30 April and 1 May holiday is very busy.
01Weather
Highs climb from the low to the upper twenties through the month and nights stay mild. Rainfall increases a little and short showers appear, but the persistent winter drizzle fades. Visibility improves, especially in the second half.
02Crowds and holidays
The Hung Kings' Commemoration (a lunar date, usually in April) and especially Reunification Day on 30 April with Labour Day on 1 May bring one of the year's biggest domestic rushes. Prices jump, buses sell out and the boats are packed. Plan around those dates or book well ahead.
03On the water
Lan Ha Bay is usually calm and the light is soft. The sea reaches about 23–24 °C by late April, fine for a quick dip from the boat, still brisk for long swims.
?Questions people ask
Is April a good time for Lan Ha Bay?
Yes. Calm seas, softer light and fewer boats than in summer make it a good month, apart from the end-of-month holiday.
Is it hot in April?
Warm rather than hot, around 25 °C by day late in the month.