Weather in Thailand in April

April climate overview

Daytime highs across Thailand in April run from 29.8°C (Phuket) to 35.7°C (Chiang Mai). In Chiang Mai about 100% of April days reach 25°C. Nights average 25.9°C; the coldest 10% of nights in Phuket fall to 25°C or below.

Rainfall in April

Expect around 15 rainy days (1 mm or more) in April, with Chiang Mai the driest (5 days) and Krabi the wettest (23 days). The wettest April at Chiang Mai between 1991 and 2020 was 2020 with 143 mm; the driest was 2001 with 0 mm.

Sea temperature

The sea averages 30.2°C around Thailand in April - warmest at Krabi (30.4°C). That is comfortable for swimming.

Sunshine and daylight

Around 4.9 hours of sunshine a day on average, out of 12.4 hours of daylight (sunshine estimated from cloud cover).

April against the rest of the year in Thailand

April is the 1st warmest month of the twelve in Thailand. It is 0.4°C warmer than March and 1.3°C cooler in May. The hottest month here is April (32°C) and the coolest December (29°C).

Which part of Thailand in April?

• Most sunshine: Chiang Mai, 8.0 h a day.
• Driest: Chiang Mai, about 5 rainy days.
• Warmest sea: Krabi, 30°C.
• Hottest: Chiang Mai, 36°C by day - intense for sightseeing.
• Coolest (better for walking and cities): Phuket, 30°C.

What to pack for Thailand in April

Based on the averages: light, loose clothing and serious sun protection - midday highs sit around 32°C; a rain jacket - roughly 15 wet days; swimwear - the sea is 30°C.

Similar weather elsewhere in April

Within 1.5°C of Thailand's April daytime average: Goa (33°C, sea 29°C), Abu Dhabi (32°C, sea 26°C), Kerala (31°C, sea 30°C). See the full ranking for April.

Chiang Mai and Bangkok: less rain, more heat

Chiang Mai suits travellers who put fewer rainy days ahead of comfort in the heat. It reaches 36°C by day, the hottest destination here, but has just 5 rainy days. That is a clear trade-off: less rain to work around, but demanding conditions for long periods outdoors. Bangkok is nearly as hot at 35°C, with 11 rainy days and nights averaging 27°C, so evenings offer limited cooling. In either destination, keep strenuous plans away from midday and leave room for shaded or air-conditioned breaks. Chiang Mai's 24°C nights provide more relief, though they are still warm.

For the coast, Koh Samui has the better balance

Koh Samui is a sensible coastal choice if you want warmth without the highest daytime temperatures or the most frequent rain. Days average 30°C, with 12 rainy days, making it less wet by this measure than the other coastal options listed. Phuket also averages 30°C but has 18 rainy days, so it calls for more flexibility. Krabi and Khao Lak are harder to recommend if uninterrupted outdoor time is your priority: they have 23 and 22 rainy days respectively. That does not mean every wet day is a write-off, but beach-only plans leave less room to adapt. Choose these destinations if you are comfortable changing plans when rain arrives.

Expect warm evenings and plan around the heat

Pack for heat that continues after sunset, rather than expecting a cool evening reset. Light, loose clothing is the practical starting point, alongside sun protection and something light for rain. Keep outdoor plans flexible and make access to shade or air conditioning part of your accommodation choice. April is less suitable if your ideal holiday involves being active outdoors throughout the day without regular breaks. Rainy-day figures help with choosing a region, but they do not tell you when rain will fall or how long it will last. Avoid building your schedule around an assumed dry morning or wet afternoon.