The sea temperature at Koh Phangan (Haad Than Sadet) today is 29.8 °C (86 °F) – water as warm as a bath. The usual October average is 29.4 °C. Over the last 30 days the sea temperature has held at around 29.8 °C. Swimmable all year – the sea averages 27 °C or more in every month. Source: Sea Temp Map (seatempmap.com) – NASA MUR satellite data and the Copernicus Marine sea forecast.
| Month | Min | Avg | Max |
|---|---|---|---|
| January | 27.3°C / 81.2°F | 27.8°C / 82.1°F | 28.6°C / 83.5°F |
| February | 28.1°C / 82.5°F | 28.4°C / 83.2°F | 28.9°C / 84.1°F |
| March | 28.6°C / 83.5°F | 29.2°C / 84.5°F | 29.6°C / 85.3°F |
| April | 30.2°C / 86.4°F | 30.4°C / 86.7°F | 30.9°C / 87.6°F |
| May | 30.2°C / 86.4°F | 30.8°C / 87.4°F | 31.4°C / 88.4°F |
| June | 29.9°C / 85.9°F | 30.2°C / 86.3°F | 30.5°C / 86.9°F |
| July | 29.6°C / 85.2°F | 29.8°C / 85.7°F | 30.0°C / 85.9°F |
| August | 29.5°C / 85.0°F | 29.8°C / 85.6°F | 30.2°C / 86.4°F |
| September | 29.3°C / 84.7°F | 29.5°C / 85.1°F | 29.7°C / 85.4°F |
| October | 28.9°C / 84.0°F | 29.4°C / 84.9°F | 29.8°C / 85.6°F |
| November | 28.5°C / 83.2°F | 28.9°C / 83.9°F | 29.4°C / 84.8°F |
| December | 27.5°C / 81.5°F | 28.0°C / 82.4°F | 28.6°C / 83.4°F |
| Month | Min | Avg | Max |
|---|---|---|---|
| January | 26.5°C / 79.7°F | 26.8°C / 80.2°F | 26.9°C / 80.4°F |
| February | 26.8°C / 80.2°F | 27.1°C / 80.7°F | 27.2°C / 80.9°F |
| March | 27.5°C / 81.5°F | 27.8°C / 82.0°F | 28.0°C / 82.4°F |
| April | 28.2°C / 82.7°F | 28.6°C / 83.5°F | 28.9°C / 84.1°F |
| May | 28.4°C / 83.0°F | 28.8°C / 83.8°F | 29.1°C / 84.4°F |
| June | 28.0°C / 82.5°F | 28.5°C / 83.4°F | 28.9°C / 84.1°F |
| July | 27.8°C / 82.0°F | 28.3°C / 82.9°F | 28.7°C / 83.6°F |
| August | 27.5°C / 81.5°F | 28.1°C / 82.5°F | 28.5°C / 83.3°F |
| September | 27.3°C / 81.2°F | 27.8°C / 82.0°F | 28.1°C / 82.5°F |
| October | 26.9°C / 80.4°F | 27.4°C / 81.2°F | 27.7°C / 81.8°F |
| November | 26.7°C / 80.0°F | 27.1°C / 80.8°F | 27.3°C / 81.1°F |
| December | 26.6°C / 79.9°F | 27.0°C / 80.5°F | 27.1°C / 80.7°F |
5-year averages (2021–2025). Min/Max are typical daily lows and highs, not record extremes. (Copernicus ERA5)
Koh Phangan holidays
About 15 km north of Koh Samui in the Gulf of Thailand, Koh Phangan is best known for Haad Rin and its Full Moon Party, yet most of the island is jungle-clad hills, with quiet bays around its coast. Most visitors rent a scooter or take songthaew pick-up taxis to move between beaches, since the roads link almost every part of the island.
Beaches
Haad Rin, on the southern tip of Koh Phangan, has two beaches: Sunrise Beach, where the Full Moon Party fills the sand each month, and Sunset Beach, or Haad Rin Nai, with Leela Beach round the headland to the south. Thong Nai Pan Yai and Thong Nai Pan Noi, twin bays in the north-east, have soft sand and calm water in the dry season and suit families. On the west coast, Haad Yao and Haad Salad have sunsets and snorkelling reefs, and Bottle Beach in the north is reached by longtail boat or a steep jungle trail. The sea temperature on this page is measured at Haad Than Sadet, a small cove on the east coast.
Things to do
Than Sadet, on the east coast, has a waterfall and a stream where several Thai kings, among them King Chulalongkorn, left inscriptions on the rocks, now part of a national park. Koh Ma, an islet off Mae Haad in the north-west, is joined to the shore by a sandbar at low tide and is a popular snorkelling spot. Thong Sala, the main town and ferry pier, has a weekend walking street market, and Srithanu, on the west coast, is the centre of Koh Phangan's yoga and wellness scene. Boat trips go to Ang Thong National Marine Park and to Koh Tao for diving.
Weather and best time to visit
At Haad Than Sadet the sea stays above 27 °C / 81 °F all year, even in the coolest month.
Koh Phangan follows the Gulf of Thailand pattern: the wettest months are usually from about October to December, when the north-east monsoon brings heavy rain and choppy seas, while late winter and spring are generally drier, and the summer months bring sunshine mixed with showers. Accommodation in Haad Rin fills up and prices rise around each full moon, and some roads are steep and unpaved, so ride carefully and check that your insurance covers scooters.
Hotels and where to stay
Haad Rin is the liveliest part of Koh Phangan, Thong Sala and Srithanu are practical bases, and the north-east bays and the west coast have quieter resorts and bungalows.
Signature hotels: Cocohut Beach Resort · Anantara Rasananda Koh Phangan Villas
Airport and getting there
Koh Phangan has no airport; the usual route is a flight to Samui International Airport (USM) on Koh Samui and then a transfer to the pier for a ferry or speedboat to Thong Sala or Haad Rin; crossing times vary by route and boat, often about 30 to 60 minutes. From the mainland, buses and ferries connect Surat Thani and its airport (URT) via Donsak pier, and high-speed catamarans run from Chumphon via Koh Tao.