May brings the start of the tourist low season in Thailand with most destinations generally seeing a drop-off in visitor numbers once the Songkran holiday period is over in April. Hotels and domestic airlines in Thailand often begin to run promotions in May so there are usually some good deals available throughout the month.
Thailand weather in May
May is still the hot season in Thailand, but increasing amounts of rainfall later in the month signal the gradual transition into the rainy season. That doesn’t mean that you will see relentless rain during your stay, but be prepared for some potentially heavy downpours at any time in May. Temperatures remain hot and during a typical two week stay you can expect to see plenty of blue sky and sunshine mixed in with the showers. Humidity levels are high across the country in May and it’s a month where you are likely to appreciate the air-conditioning in your room more than ever.
| Location | Average Minimum Temp. (°C) | Average Maximum Temp. (°C) | Average Rainfall (mm) |
|---|---|---|---|
| Bangkok | 25 | 34 | 190 |
| Chiang Mai | 23 | 34 | 153 |
| Hua Hin | 25 | 33 | 105 |
| Ko Chang | 24 | 32 | 410 |
| Ko Samui | 26 | 33 | 158 |
| Krabi | 25 | 32 | 346 |
| Pattaya | 26 | 32 | 177 |
| Phuket | 25 | 32 | 345 |
Which is the best Thai island or beach resort to visit in May?
Whichever island or beach resort you opt for in May, you can expect to see some rain. Rainfall levels during the month are lower on the Gulf of Thailand coast compared to the Andaman Coast. Average rainfall levels are higher on the Andaman Coast due to the effects of the south-west monsoon. This usually blows in from the Indian Ocean during June-September, but it can sometimes start early in May. This brings higher rainfall levels to destinations including Phuket, Krabi and the Trang islands. Downpours can be torrential and may be accompanied by gusty winds and high waves. Some boat services to outlying islands in the Andaman Sea are temporarily suspended during May-October, but it should be noted that it doesn’t rain all day, every day. There is still plenty of sunshine and temperatures remain high.
The Gulf Coast of Thailand does not feel the full effect of the south-west monsoon making May a good month to visit islands including Ko Samui, Ko Pha Ngan and Ko Tao. And on the mainland, Hua Hin and the Cha Am area are also an excellent choice for a beach break. Over on the eastern seaboard there are varying levels of rainfall with amounts high on Ko Chang and comparatively low in Pattaya and Ko Samet.
A change of winds and summer storms can see jellyfish arriving in Thai waters during the rainy season. Most are relatively harmless, but box jellyfish can also show up and it is something to be aware of. Swimmers should also pay heed to any warning flags on beaches. There are fatalities every year because swimmers ignore the no swimming flags and get caught in rip tides.
May events and festivals in Thailand
The onset of the rainy season in May/June has traditional significance in Thailand. The importance of rice to the country is celebrated with the Royal Ploughing Ceremony in Bangkok. There is no fixed date for this event, but it usually falls in May. The rice-growing heartlands in the north-east of Thailand also hold their own unique festivities ahead of the rice planting season with home-made rockets launched and boisterous parties held to encourage a good crop.
There are a number of important Buddhist holidays throughout the year, but the most significant in Thailand is Visakha Bucha Day. The exact date depends on the full-moon, but often falls in May. Visakha Bucha Day commemorates three defining events in the life of the Lord Buddha: the day on which he was born, reached his enlightenment 35 years later and the day he died and entered Nirvana 45 years after that. Visakha Bucha Day is a public holiday in Thailand and there are restrictions in place on alcohol sales. The first of May is also a public holiday for Labour Day.
