April marks a transition month between monsoon systems as much of Thailand comes under the influence of the Southeast monsoon that builds up through April and May, bringing higher humidity and afternoon downpours.

April is still high season for most hotels in on the West coast of Thailand, including Phuket, Krabi, Khao Lak and Koh Lanta. Some hotels reduce prices from the middle of April and the second half of April can be an excellent time for good deals right at the start of low season.

On Koh Samui temperatures have risen a little bit but the island still usually receives relatively little rain during this time of year.

The climate in Bangkok and in the north of Thailand reflects that of the West coast.