Koh Samui weather
Loading live data…Latest for Koh Samui: European (ECMWF): 28° Light drizzle · American (NOAA GFS): 30° Overcast · German (DWD ICON): 28° Overcast.
The weather map: all three models at once
European, American, German side by side around Koh Samui and nearby towns.Live rain radar →Hourly forecast: next 14 hours
consensus of the three modelsRain in the next 24 hours, model by model
each model's own hourly precipitation, side by sideLoading the three models…
10-day forecast, out to 14 days
where the models agree, and where they splitHeading to Koh Samui? Koh Samui, Thailand, sits at 9.5°N in a tropical climate zone. Before you lock in outdoor plans, compare how the three global models - European (ECMWF), American (GFS) and German (ICON) - forecast Koh Samui right now. Where they agree you can trust it; the days they split are exactly when a single weather app is least reliable. For a beach trip the rain and wind columns below matter most - that is what makes or breaks a day by the sea.
Best time to visit Koh Samui
The most comfortable time to visit Koh Samui is usually January, February, March and April, when daytime highs sit in the pleasant 24-33°C range and the heaviest November rain is behind you.
Koh Samui weather by month
what to expect in Koh Samui through the year, 1991-2020 normals, Ko Samui (WMO)Here is Koh Samui's typical weather in each month: the average daytime high and overnight low in °C, how each month feels, and the wettest month marked. Use it to plan any trip to Koh Samui by season.
Koh Samui compared with Sydney
30-year averages: daytime highs month by month, rain and sunlightWarmer through the year
average daytime high: Koh Samui 31°C, Sydney 23°C
Rain over a year
Koh Samui 1,994 mm, Sydney 1,148 mm
Sunlight vs a clear sky
solar energy reaching the ground as a share of a cloudless day, averaged over the year (not sunshine hours)
On 30-year averages Koh Samui runs 8°C warmer than Sydney, with every month between +1°C and +15°C. Over a year it gets 74% more rain than Sydney.
Month by month in numbers
| Month | Koh Samui | Sydney | Difference | Sunlight, Koh Samui | Sunlight, Sydney |
|---|---|---|---|---|---|
| January | 29°C | 27°C | +2°C | 80% | 75% |
| February | 29°C | 28°C | +1°C | 87% | 73% |
| March | 30°C | 26°C | +4°C | 87% | 75% |
| April | 32°C | 24°C | +8°C | 84% | 77% |
| May | 33°C | 22°C | +11°C | 77% | 79% |
| June | 33°C | 18°C | +15°C | 75% | 74% |
| July | 32°C | 18°C | +14°C | 74% | 80% |
| August | 32°C | 20°C | +12°C | 74% | 82% |
| September | 32°C | 22°C | +10°C | 73% | 82% |
| October | 31°C | 24°C | +7°C | 69% | 77% |
| November | 30°C | 25°C | +5°C | 69% | 74% |
| December | 29°C | 27°C | +2°C | 73% | 74% |
Daytime highs and lows on this page are 1991-2020 averages. Koh Samui: station normals from Ko Samui (WMO), rain included. Sydney: station normals from Sydney Observatory Hill (WMO), rain included. Sunlight vs a clear sky is NASA POWER's long-term average of the solar energy reaching the ground as a share of a cloudless day; it compares cloudiness and is not a count of sunshine hours. Sydney stands in for Australia here; other cities have their own climate tables.