Koh Samui Weather Forecast
Koh Samui weather: 77°F, light drizzle. Hourly forecast, 14-day outlook, UV, air quality and the best time to visit.
Risk assessment for Koh Samui
Derived from the current forecast window - not an official warning.
Peak gusts of 25 mph and 0 thunderstorm days in the next 16 days.
Wettest single day forecast at 1,0 in, 7,0 in across the window. Flash flooding risk rises sharply above 50 mm in a day.
Active alerts for Koh Samui
Derived from the forecast. No official alert feed is wired for this country yet.
16-day forecast for Koh Samui
Daily highs and lows, precipitation and UV.
| Day | Conditions | High / Low | Precip | Wind | UV |
|---|---|---|---|---|---|
| Fri, Oct 23 | 🌦️ Drizzle | 86° / 75° | 94% · 0,1 in | 5 mph | 8 |
| Sat, Oct 24 | 🌦️ Light showers | 81° / 72° | 80% · 0,3 in | 6 mph | 8 |
| Sun, Oct 25 | 🌦️ Light showers | 80° / 72° | 80% · 0,3 in | 8 mph | 8 |
| Mon, Oct 26 | 🌧️ Showers | 78° / 71° | 84% · 0,7 in | 6 mph | 8 |
| Tue, Oct 27 | 🌧️ Showers | 76° / 71° | 80% · 0,9 in | 8 mph | 7 |
| Wed, Oct 28 | 🌦️ Light showers | 77° / 72° | 90% · 0,3 in | 8 mph | 2 |
| Thu, Oct 29 | 🌦️ Light showers | 80° / 70° | 92% · 0,4 in | 7 mph | 7 |
| Fri, Oct 30 | 🌧️ Showers | 77° / 72° | 99% · 1,0 in | 8 mph | 3 |
| Sat, Oct 31 | 🌦️ Drizzle | 79° / 72° | 94% · 0,4 in | 8 mph | 8 |
| Sun, Nov 1 | 🌦️ Light showers | 78° / 71° | 94% · 0,4 in | 5 mph | 7 |
| Mon, Nov 2 | 🌦️ Light showers | 76° / 70° | 96% · 0,5 in | 7 mph | 3 |
| Tue, Nov 3 | 🌦️ Drizzle | 79° / 69° | 94% · 0,3 in | 7 mph | 8 |
| Wed, Nov 4 | 🌦️ Drizzle | 78° / 70° | 98% · 0,3 in | 6 mph | 8 |
| Thu, Nov 5 | 🌦️ Drizzle | 80° / 72° | 92% · 0,1 in | 5 mph | 8 |
| Fri, Nov 6 | 🌧️ Heavy drizzle | 79° / 70° | 90% · 0,2 in | 5 mph | 8 |
| Sat, Nov 7 | 🌦️ Light showers | 76° / 70° | 70% · 0,8 in | 15 mph | 2 |
What this means for Koh Samui
Today is slightly warmer than average for October. The forecast high of 86°F is 4.7°F above the 81°F typical for this month.
A 94% chance means rain is expected over most of the area. Plan indoor alternatives.
Wet roads are likely; braking distances roughly double in heavy rain.
Within 15 degrees of the equator, day length barely changes all year; seasons are defined by rain, not temperature.
Northern Hemisphere, so peak summer falls in June to August.
The gap between the warmest and coldest month averages 37°F - an unusually even climate through the year.
See the Koh Samui forecast by time range
Koh Samui weather - more answers
Explore Koh Samui
Every topic we hold for this place, and the same topic for the places around it.
Weather for related places
Frequently asked questions
Where is Koh Samui?
Koh Samui is an island in Thailand. Its coordinates are 9.512, 100.0136. It lies in Asia.
What is the weather like in Koh Samui right now?
It is currently 77°F (25°C) with light drizzle. Humidity is 86% and wind is 4 mph.
When is the best time to visit Koh Samui?
January, February, March and April offer the most comfortable conditions in Koh Samui, which has a temperate climate. October, November and December are usually the hardest months for outdoor plans.
What time zone is Koh Samui in?
Koh Samui observes Asia/Bangkok (UTC+07:00). The local time is 6:27 AM.
What is the nearest airport to Koh Samui?
The closest airports are Phuket International Airport (HKT), 151 mi away and Suvarnabhumi Airport (BKK), 293 mi away.
What are the top things to do in Koh Samui?
Popular options include Khao Sok National Park, Railay Beach, Maya Bay and Langkawi.
Related articles
Data sources and methodology
| Place data | USPOTUS Atlas dataset (islands) - coordinates, hierarchy and facts. |
|---|---|
| Forecast and observations | Open-Meteo (ECMWF and national models). |
| Air quality and pollen | Copernicus CAMS via Open-Meteo. US AQI scale. |
| Climate averages | ERA5 reanalysis via the Open-Meteo archive, aggregated over 3 years. |
| Method | Scores, comparisons and advice on this page are computed from the inputs above. Distances are straight-line. Nothing is estimated where data is missing - the block is simply not shown. |
Last updated October 24, 2026 at 6:27 AM local time. Live blocks refresh every 15 minutes; climate averages monthly.
