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📊 Monthly Climate Overview
| Month | Max °C | Min °C | Rain mm | Rain Days | Sun h | Wind km/h | Sea °C |
|---|---|---|---|---|---|---|---|
| Jan | 28°C | 25°C | 125.6 mm | 16 | 10.3 h | 18.1 km/h | 28°C |
| Feb | 28.6°C | 25.2°C | 44 mm | 11 | 10.7 h | 18.7 km/h | 28.5°C |
| Mar | 30°C | 26°C | 37.3 mm | 10 | 11.0 h | 16.6 km/h | 28.9°C |
| Apr | 30.9°C | 27°C | 108.2 mm | 14 | 10.9 h | 14.7 km/h | 30.9°C |
| May | 31.2°C | 27.2°C | 106.7 mm | 20 | 10.7 h | 15.4 km/h | 31.5°C |
| Jun | 31.1°C | 27°C | 75 mm | 16 | 10.0 h | 17.6 km/h | 30.8°C |
| Jul | 30.9°C | 26.7°C | 85 mm | 17 | 9.6 h | 19.3 km/h | 30.5°C |
| Aug | 30.9°C | 26.6°C | 70.1 mm | 17 | 9.7 h | 19.6 km/h | 30.3°C |
| Sep | 29.9°C | 26.1°C | 143.1 mm | 20 | 8.7 h | 18.4 km/h | 30.2°C |
| Oct | 28.9°C | 25.6°C | 221.6 mm | 27 | 8.9 h | 15.3 km/h | 30.5°C |
| Nov | 28.4°C | 25.4°C | 283.8 mm | 26 | 8.7 h | 16.7 km/h | 29.6°C |
| Dec | 28.1°C | 25.3°C | 208.7 mm | 20 | 9.7 h | 19.6 km/h | 28.6°C |
📖Climate & Best Time to Visit Ko Samui
Ko Samui (Thailand) has a tropical climate with an annual average of around 28 °C. Daytime highs average 30 °C, while nights cool to about 26 °C. The destination sees roughly 1509 mm of rainfall per year and 9.9 hours of sunshine per day on average.
Coconut-palm island in the Gulf of Thailand — Chaweng Beach for buzz, calmer Mae Nam, the golden Big Buddha and snorkelling in Ang Thong Marine Park.
Warm and tropical year-round — daily highs stay between 28 and 31 °C. The real variable is rain: March with only 10 rainy days is ideal, while October (27 rainy days) brings monsoon showers.
Rainfall varies through the year: peaks in October (27 rainy days), driest month is March (10).
🎟️ Top activities in Ko Samui
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Frequently asked questions about Ko Samui
When is the best time to visit Ko Samui?
The best time to visit Ko Samui: February to March – best in March (avg. 28.0 °C, 10 rainy days). Based on the monthly values for 2014 to 2023.
What are the temperatures in Ko Samui?
The warmest month is May with an average of 29.2 °C and daytime highs around 31.2 °C. The coldest month is January with an average of 26.5 °C and night-time lows around 25.0 °C.
How many rainy days does Ko Samui have?
October has the most rainy days with 27 rainy days. The driest month is March with 10 rainy days.
What is the sea temperature near Ko Samui?
The water is warmest in May at an average of 31.5 °C and coolest in January at 28.0 °C.