The Thailand resorts with the warmest sea water temperature in September are Ko Li Pe, Koh Lanta and Phi Phi.
Below you can see a list of all popular Thailand resorts and information about sea water temperature in September for the last two years.
| Resort Name | September 2026 | September 2025 | September 2024 |
|---|---|---|---|
| Ko Li Pe | 91.1°F | 89.8°F | 89.6°F |
| Koh Lanta | 90.3°F | 88.8°F | 88.5°F |
| Phi Phi | 90.3°F | 88.6°F | 88.9°F |
| Krabi | 90.2°F | 88.6°F | 89.0°F |
| Pattani | 90.2°F | 89.5°F | 89.6°F |
| Narathiwat | 90.1°F | 89.9°F | 89.7°F |
| Bangkok | 90.0°F | 88.8°F | 89.7°F |
| Hat Yai | 90.0°F | 90.0°F | 89.8°F |
| Koh Lan | 89.8°F | 88.8°F | 90.0°F |
| Cape Panwa | 89.8°F | 88.1°F | 88.6°F |
| Pattaya | 89.7°F | 88.6°F | 89.7°F |
| Cha-am | 89.7°F | 89.1°F | 90.0°F |
| Hua Hin | 89.7°F | 89.1°F | 90.0°F |
| Jomtien | 89.6°F | 88.6°F | 89.7°F |
| Phuket | 89.5°F | 87.8°F | 88.5°F |
| Surin Beach | 89.5°F | 87.7°F | 88.4°F |
| Bang Tao Beach | 89.5°F | 87.7°F | 88.4°F |
| Kamala Beach | 89.5°F | 87.7°F | 88.4°F |
| Kalim Beach | 89.5°F | 87.7°F | 88.4°F |
| Rawai Beach | 89.4°F | 87.8°F | 88.4°F |
| Nai Harn Beach | 89.4°F | 87.8°F | 88.4°F |
| Patong Beach | 89.4°F | 87.7°F | 88.4°F |
| Kata Beach | 89.4°F | 87.7°F | 88.4°F |
| Karon Beach | 89.4°F | 87.7°F | 88.4°F |
| Nai Yang Beach | 89.4°F | 87.8°F | 88.3°F |
| Lamai Beach | 89.3°F | 89.0°F | 89.8°F |
| Mai Khao Beach | 89.3°F | 87.8°F | 88.2°F |
| Taling Ngam Beach | 89.3°F | 88.9°F | 89.5°F |
| Chaweng Beach | 89.2°F | 88.9°F | 89.7°F |
| Samui | 89.1°F | 88.8°F | 89.6°F |
| Rayong | 89.1°F | 88.4°F | 89.4°F |
| Mae Nam Beach | 89.1°F | 88.7°F | 89.5°F |
| Bo Phut Beach | 89.1°F | 88.7°F | 89.5°F |
| Choeng Mon Beach | 89.1°F | 88.7°F | 89.6°F |
| Surat Thani | 89.0°F | 88.5°F | 88.5°F |
| Ko Phangan | 88.9°F | 88.6°F | 89.4°F |
| Phangan | 88.9°F | 88.6°F | 89.3°F |
| Samet | 88.9°F | 88.2°F | 89.2°F |
| Trat | 88.6°F | 88.0°F | 88.3°F |
| Khao Lak | 88.6°F | 87.5°F | 87.6°F |
| Ko Wai | 88.5°F | 88.1°F | 88.9°F |
| Ko Mak | 88.4°F | 88.1°F | 89.0°F |
| Tao | 88.4°F | 88.5°F | 89.4°F |
| Koh Kood | 88.3°F | 88.0°F | 89.0°F |
| Koh Chang | 88.3°F | 88.2°F | 88.9°F |
| Chumphon | 88.3°F | 87.7°F | 88.7°F |
| Prachuap Khiri Khan | 88.2°F | 87.9°F | 89.2°F |
| Similan | 87.9°F | 87.0°F | 87.8°F |
Please see following sea water temperature averages charts for the warmest Thailand resorts in September.
You can also get the same information for the every other month of the year when the average sea water temperature is greater then 70°F.
Thailand Resorts:
NAME
F°
| Bang Tao Beach |  |
+84 |
| Bangkok |  |
+80 |
| Cape Panwa | |
+84 |
| Hua Hin | |
+80 |
| Karon Beach | |
+84 |
| Kata Beach | |
+84 |
| Khao Lak | |
+82 |
| Koh Chang | |
+86 |
| Nai Yang Beach | |
+84 |
| Pattaya | |
+78 |
| Phangan | |
+86 |
| Phi Phi | |
+88 |
| Phuket | |
+84 |
| Samet | |
+86 |
| Samui | |
+86 |
