Koh Samui Weather in October
October in Koh Samui brings high temperatures, with highs of 29°C (84°F) and nights dropping to 26°C (79°F). It's the rainiest month of the year, so come prepared with waterproof gear.
Rainfall in Koh Samui in October
Prepare for intense rain this month, as it marks the peak rainfall period. Having a poncho will keep you dry through the downpours. Typically, about 20 days will experience rainfall, with an average of 296 mm (12 in) for the month. This is a wet month with frequent and often heavy showers. Both the number of rain days and the total rainfall are high.
Temperature in Koh Samui in October
In October, Koh Samui gets high temperatures, with highs of 29°C (84°F). Nights cool to around 26°C (79°F). This gives the month a fairly typical daily rhythm, with warmer afternoons and more comfortable nights. With overnight lows of 26°C (79°F), nights stay very warm. Air conditioning makes a real difference if you're sensitive to heat. A cold shower before bed can also help you get to sleep more comfortably.
Sunshine in Koh Samui in October
With about 146 hours of sunshine, the area enjoys a nice balance of sun and overcast, creating a pleasant environment.
Average water temperature in October
The water reaches 29°C (84°F) this month. It's on the warm side, which suits people who prefer that, but don't expect a cooling dip if the air temperature is also high.Our weather planner can help you find worldwide destinations with pleasant weather during this period. January and February typically offer the best weather for Koh Samui.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Thailand, check out our Koh Samui's climate page.
Koh Samui Temperature in October
Min Temperature
26°C (79°F)
Max Temperature
29°C (84°F)
Water Temperature
29°C (84°F)
Chance of Rain
67%
Precipitation
296 mm (12 in)
Rainy days
20 days
Humidity
85%
Sunshine
146 hours
Percentage Sunshine
Daily Historical Temperatures
47-year average (1976-2025)
Based on our historical records, temperatures in Koh Samui typically stay consistent throughout October, with daily highs averaging around 29°C (84°F). Nights are warm, with lows around 25°C (77°F).
Average temperatures in October
Daily Historical Precipitation
47-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in October
Historical weather for Koh Samui in October
Browse day-by-day weather records for Koh Samui spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Koh Samui historical weather extremes in October
Based on 39 years of weather observations (1986-2025), these are the most extreme conditions recorded in Koh Samui.
- The warmest day in October was on October 19, 1988, with a maximum of 37°C (99°F).
- Koh Samui experienced its chilliest October day on October 17, 1993, reaching only 25°C (77°F).
- Koh Samui registered its coldest October night on October 22, 2022, with temperatures dropping to 21°C (70°F).
Best Places in Thailand in October
Find out more about the weather in Thailand and which places have the best travel conditions in this month. See all of Thailand in October →
perfect weather
pleasant
tolerable
unpleasant
poor
What to Wear in Koh Samui in October
Warm but pleasant conditions in Koh Samui in October. Focus on lightweight, maybe with natural fabrics, cotton blend shirts, comfortable shorts, and breathable footwear. A light cover-up for sun protection is smart too. It's going to pour! Pack a good poncho and prepare for very wet conditions. With water temperatures around 29°C (84°F), swimming conditions are excellent. Pack your swimsuit, goggles, and maybe some water shoes. Sunglasses could come in handy during the sunnier parts of your trip.What To Do in Koh Samui in October
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Thailand, check out our Koh Samui's climate page.
Temperature Rainfall Sunshine Humidity Water Temp
See the full Koh Samui climate overview or explore weather in Thailand.
