Weather in Thailand in June

June climate overview

Daytime highs across Thailand in June run from 28.8°C (Phuket) to 32.3°C (Bangkok). In Bangkok about 100% of June days reach 25°C. Nights average 25.7°C; the coldest 10% of nights in Phuket fall to 25°C or below.

Rainfall in June

Expect around 22 rainy days (1 mm or more) in June, with Koh Samui the driest (19 days) and Krabi the wettest (25 days). The wettest June at Bangkok between 1991 and 2020 was 1994 with 238 mm; the driest was 1997 with 51 mm.

Sea temperature

The sea averages 29.8°C around Thailand in June - warmest at Bangkok (30.1°C). That is comfortable for swimming.

Sunshine and daylight

Around 1.6 hours of sunshine a day on average, out of 12.8 hours of daylight (sunshine estimated from cloud cover).

June against the rest of the year in Thailand

June is the 5th warmest month of the twelve in Thailand. It is 0.8°C cooler than May and 0.5°C cooler in July. The hottest month here is April (32°C) and the coolest December (29°C).

Which part of Thailand in June?

• Most sunshine: Phuket, 1.9 h a day.
• Driest: Koh Samui, about 19 rainy days.
• Warmest sea: Bangkok, 30°C.
• Hottest: Bangkok, 32°C by day - intense for sightseeing.
• Coolest (better for walking and cities): Phuket, 29°C.

What to pack for Thailand in June

Based on the averages: light, loose clothing and serious sun protection - midday highs sit around 30°C; a rain jacket - roughly 22 wet days; swimwear - the sea is 30°C.

Similar weather elsewhere in June

Within 1.5°C of Thailand's June daytime average: Sousse (32°C, sea 22°C), Orlando (31°C), Kusadasi (31°C, sea 23°C), Ho Chi Minh City (31°C), Montego Bay (31°C, sea 29°C). See the full ranking for June.

Which part of Thailand is best in June?

Koh Samui offers the most favourable balance for a beach stay: daytime temperatures of 30°C, sea temperatures to match and fewer rainy days than the other destinations compared. The catch is that its 19 rainy days still make waterproofs and flexible plans sensible. Krabi and Khao Lak each have 24 rainy days, so they are less suitable if keeping outdoor plans is your priority. Phuket sits between them and Koh Samui for rain frequency. For an inland stay, Chiang Mai has slightly fewer rainy days than Bangkok and cooler nights, making it the better choice if you want some relief from the heat after dark.

Expect hot days and little cooling after dark

Bangkok is the hottest option at 32°C by day, so allow yourself breaks rather than packing outdoor time tightly around midday. Chiang Mai is close behind at 31°C, though its 24°C nights offer more cooling than Bangkok's 26°C. Koh Samui stays particularly warm after dark at 27°C, which makes light sleepwear and a cooled room useful priorities. Loose, lightweight clothing makes sense throughout the country, with a light waterproof layer for rain. Compared with London's June daytime average of 20°C, Thailand will feel distinctly hotter. Even the milder daytime options, including Phuket, Krabi and Khao Lak, average 29°C rather than offering genuinely cool conditions.

Plan for rain rather than reliable sunshine

June suits travellers who are comfortable adjusting their day to the weather, rather than those who want dependable sunbathing conditions. The country sunshine average is just 1.6 h, so warmth should not be mistaken for clear skies. Keep outdoor plans flexible and have indoor alternatives in mind. Rain-day figures tell you how often rain occurs, not that every wet day is a complete washout, but they do justify bringing rain protection for yourself and your belongings. Sea temperatures of 29°C to 30°C mean cold water is unlikely to be the main obstacle to a swim; local weather and water conditions still need checking before entering.