The weather in Thailand in May is classic tropics: hot and humid. Early May is still the hottest time of year across Thailand. Daytime highs reach 32–34°C (90–94°F) with 75% humidity, so it often feels even hotter.
According to the Thai Meteorological Department, the rainy season also begins around mid-May. Most destinations see 12–18 rainy days, but showers tend to be short and dramatic, often in the late afternoon or evening.
A typical May day? Sunny or partly cloudy until about 4 p.m., when dark clouds roll in, the sky opens up with a tropical thunderstorm for about an hour, and then you get a cooler evening.
Is May Right for You?
May works best for travelers who are flexible and don't mind planning around the weather. Expect hot, humid days and short but intense bursts of rain—often in the late afternoon.
Across much of Thailand, these showers are easy to work around, but conditions vary: on the Andaman side, rough seas can occasionally delay or cancel boat tours.
The upside: Crowds thin out after April's holidays, and hotel and airfare prices can drop 20–40%. Couples find quieter beaches and attractive spa offers, while families have an easier time booking top resorts with strong kids' programs. And if you're a fruit lover, May's durian and mango season is a delicious bonus.
Travel smart: Keep mornings light and afternoons flexible, choose refundable tours, and for the most reliable beach weather, stick to the Gulf coast.
More tips on planning a trip to Thailand.
Where to Go in Thailand in May—Best Weather by Region
Gulf Islands (Koh Samui, Koh Phangan, Koh Tao & Hua Hin)
When travelers ask where to find the most reliable beach weather in May, the Gulf side is our go-to recommendation. The southwest monsoon hasn't fully set in here, so you still get long sunny spells between short showers.
For couples, private-pool villas with spa packages feel romantic yet affordable compared to high season. Families appreciate the calmer bays, which are safer for kids, plus resorts here often have excellent kids' programs.
Highlights:
- Koh Samui: Easier access, luxury resorts, destination spas, and sheltered bays—ideal for couples and families.
- Koh Tao: A quieter vibe with casual diving, though visibility varies in May.
- Hua Hin: The driest coastal weather this month, plus golf courses, wild elephant spotting, and family-friendly resorts.
Things to watch out for: Peak-season marine life and crystal-clear snorkeling aren't guaranteed—underwater visibility can be unpredictable, and some dive sites don't shine in May.
Andaman Coast (Phuket, Krabi, Phi Phi, Khao Lak)
By May, this coast turns wetter and windier. Treat it as a slow-travel destination with a focus on all-weather activities: spa days, Thai cooking classes, historic old towns, and dining with panoramic views. Phuket is the most developed base, with the widest range of choices.
Things to watch out for:
Some beaches may have red-flag swimming warnings on a rainy day.
Think of island-hopping as a bonus for calm-sea days rather than a guaranteed activity. Because seas can be rough, causing last-minute cancellations (we experienced this firsthand on a May field trip).
The Similan Islands close from mid-May for conservation and safety, so diving there won't reopen until next season.
Bangkok & Central Thailand
Temperatures in central Thailand are similar to other regions, but it sees the least rain in May—around 13 days of showers compared to 17+ on the Andaman coast—making it easier to plan sightseeing.
Bangkok's a great spot for a quick 2–3 day stop. There's lots to do indoors, but don't miss the street food in Chinatown and the floating markets. The top Thai attractions, the Grand Palace, Wat Pho, and Wat Arun, are amazing—but heads up, it gets crowded fast (we saw it packed by 9:30 a.m. in May).
Kanchanaburi sees less rainfall in the central area. Its waterfalls and floating bungalows are perfect cool retreats. WWII history sites like the Death Railway and Hellfire Pass remain moving even in the rain.
Things to watch out for: Ayutthaya and Lopburi are rewarding historical day trips, but shade is scarce and afternoons can be blisteringly hot—start early and wrap up by 2 p.m.
Chiang Mai & the North
May is one of the most rewarding times for cultural trips up north. The rains clear away April's haze, making your visits more pleasant.
In Chiang Mai, you may find fewer crowds at alms-giving ceremonies. Ethical elephant experiences are easier to book, and the Visakha Bucha holiday—often in May—brings beautiful candlelit processions.
Chiang Rai offers a quieter, more rural feel, plus famous temples like Wat Rong Khun. Luxury hideaways like the Four Seasons Golden Triangle start lowering rates—perfect if you're after a secluded, romantic jungle escape.
Things to watch out for: May brings on-and-off showers that leave trails slick, and high viewpoints (like Doi Inthanon) often turn misty after rain. Plan early starts and keep a weather buffer: pick lower-elevation hikes or paved cycling routes, and keep rain-friendly backups—waterfalls (they're fuller after rain), local ethical markets, and village visits.
What to Pack in May
Pack breathable linen/cotton, a sun hat, high-SPF reef-safe sunscreen, and a light rain jacket or compact umbrella. Quick-dry shoes or sandals with grip help on slick streets.
Average Temperatures and Rainfall in Thai Cities in May
| Destination | Min–Max Temp (°C/°F) | Rainfall (mm) | Rainy Days |
|---|---|---|---|
| Chiang Mai | 24°C–34°C / 76°F–93°F | 134.6 mm | 14.5 d |
| Chiang Rai | 23°C–32°C / 74°F–90°F | 134.6 mm | 14.8 d |
| Sukhothai | 27°C–35°C / 81°F–95°F | 142.2 mm | 14.1 d |
| Bangkok | 27°C–34°C / 80°F–94°F | 114.3 mm | 14.2 d |
| Phatthaya | 27°C–32°C / 81°F–90°F | 121.9 mm | 14.7 d |
| Hua Hin | 27°C–33°C / 80°F–92°F | 91.4 mm | 13.3 d |
| Ayutthaya | 27°C–35°C / 80°F–95°F | 114.3 mm | 14.3 d |
| Kanchanaburi | 27°C–35°C / 80°F–95°F | 109.2 mm | 12.9 d |
| Krabi | 24°C–32°C / 76°F–90°F | 203.2 mm | 17.1 d |
| Ko Phuket | 26°C–32°C / 78°F–90°F | 223.5 mm | 17.5 d |
| Ko Samui | 27°C–33°C / 81°F–91°F | 132.1 mm | 15.4 d |
(Data source: Weather Spark. Averages vary by source and year, but these are solid planning baselines for the weather in Thailand in May.)
FAQ – Thailand in May
1. Is May a good time to visit Thailand?
Yes—especially for budget-conscious travelers. May is a transition month from dry to wet; travel is possible, crowds are smaller, and prices are often lower. Find out more information about the best time to visit Thailand.
2. What are the best places to visit on my first trip to Thailand?
For iconic experiences with mostly manageable May weather, Bangkok, Chiang Mai, and Koh Samui are top picks. Check out our customizable itinerary of these three cities.
3. Are tours and attractions fully operational?
Most are open, but some hiking trails or sea-based activities may be affected by weather.
4. Are local festivals or holidays worth planning around?
Yes, it may include cultural events like Visakha Bucha in Bangkok, Chiang Mai, and Phuket. Participating in offers unique experiences, but can affect crowds.
Monthly Weather and Travel Information for Thailand
Learn about the weather in Thailand for 12 months and find out the best places to visit each month.
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