🇹🇭 Weather in Koh Samui in May
This is what the weather in Koh Samui (Thailand) was like in May in 2017–2026.
Key facts at a glance
Avg. daytime high
30.3 °C
29.6 °C – 31.7 °C
Avg. night-time low
28.8 °C
28.2 °C – 30.0 °C
Avg. rain days in period
27.5
89 % of days · ≥ 1.0 mm
Avg. precipitation in period
204 mm
132 mm – 467 mm
Avg. cloud cover
88 %
This data source has no sunshine hours – average cloud cover shown instead.
Avg. sea temperature
–
Sea temperature unavailable for today (daily limit).
Extremes: Highest temperature 33.5 °C (2 May 2024) · Lowest temperature 27.2 °C (28 May 2022) · Avg. daily peak wind 17 km/h
Weather mix of all days
- 2Sunny
- 11Partly cloudy
- 22Cloudy
- 129Light rain
- 146Rain
Summary
- On average 30.3 °C during the day and 28.8 °C at night.
- On average 27.5 rain days (Rain day = at least 1.0 mm of precipitation) with 204 mm of precipitation in total.
- Prevailing: Rain.
- Warmest year: 2024 (avg. 31.7 °C), coolest: 2022 (avg. 29.6 °C).
- Wettest year: 2022 (467 mm), driest: 2020 (132 mm).
- Extremes: 33.5 °C on 2 May 2024 and 27.2 °C on 28 May 2022.
Overall values from all 10 years. How is this calculated?
Charts
Temperatures per year
Average over your travel period
Precipitation & rain days
Year by year
2026
Avg. max30.0°Avg. min28.6°- Rain days
- 30 Rain days
- Precipitation
- 240 mm
- Avg. cloud cover
- 90 % cloudy
- Sea temperature
- –
Max 31.3 °C · Min 28.1 °C
2025
Avg. max30.0°Avg. min28.7°- Rain days
- 29 Rain days
- Precipitation
- 205 mm
- Avg. cloud cover
- 92 % cloudy
- Sea temperature
- –
Max 31.6 °C · Min 27.4 °C
2024
Avg. max31.7°Avg. min30.0°- Rain days
- 21 Rain days
- Precipitation
- 139 mm
- Avg. cloud cover
- 89 % cloudy
- Sea temperature
- –
Max 33.5 °C · Min 28.8 °C
2023
Avg. max31.0°Avg. min29.2°- Rain days
- 24 Rain days
- Precipitation
- 141 mm
- Avg. cloud cover
- 78 % cloudy
- Sea temperature
- –
Max 32.5 °C · Min 28.5 °C
2022
Avg. max29.6°Avg. min28.2°- Rain days
- 30 Rain days
- Precipitation
- 467 mm
- Avg. cloud cover
- 92 % cloudy
- Sea temperature
- –
Max 30.8 °C · Min 27.2 °C
2021
Avg. max29.9°Avg. min28.5°- Rain days
- 27 Rain days
- Precipitation
- 187 mm
- Avg. cloud cover
- 89 % cloudy
- Sea temperature
- –
Max 31.1 °C · Min 27.6 °C
2020
Avg. max30.5°Avg. min29.0°- Rain days
- 24 Rain days
- Precipitation
- 132 mm
- Avg. cloud cover
- 81 % cloudy
- Sea temperature
- –
Max 31.5 °C · Min 27.8 °C
2019
Avg. max30.7°Avg. min28.7°- Rain days
- 30 Rain days
- Precipitation
- 157 mm
- Avg. cloud cover
- 87 % cloudy
- Sea temperature
- –
Max 32.2 °C · Min 28.0 °C
2018
Avg. max29.9°Avg. min28.7°- Rain days
- 30 Rain days
- Precipitation
- 169 mm
- Avg. cloud cover
- 87 % cloudy
- Sea temperature
- –
Max 30.6 °C · Min 27.7 °C
2017
Avg. max30.1°Avg. min28.8°- Rain days
- 30 Rain days
- Precipitation
- 204 mm
- Avg. cloud cover
- 93 % cloudy
- Sea temperature
- –
Max 31.0 °C · Min 28.2 °C
Frequently asked questions
- How warm is it in Koh Samui in May?
- Daytime highs averaged 30.3 °C, night-time lows 28.8 °C. The highest value of the past 10 years was 33.5 °C (2 May 2024), the lowest 27.2 °C (28 May 2022).
- How often does it rain in Koh Samui in May?
- On average there were 27.5 rain days (at least 1 mm) with 204 mm of precipitation in total.
Check your exact travel dates
Choose your travel period – we show the weather for exactly those days.
Other destinations in May
Data sources
- Weather data
- Data obtained from the NASA Langley Research Center (LaRC) POWER Project funded through the NASA Earth Science/Applied Science Program
Reanalysis (weather model constrained by observations) on a coarse grid of about 50 km. Values represent a large area and can differ from local conditions, especially on islands, coasts and in mountains. No sunshine duration.
Reanalysis (weather model constrained by observations)
Reanalysis values represent a grid cell (approx. 25–50 km) and may differ from local measurements on coasts, islands and in mountains. - Sea temperature
- MUR SST data were provided by JPL under support by NASA MEaSUREs program; accessed via NOAA CoastWatch ERDDAP
Daily multi-scale ultra-high resolution (≈ 1 km) analysis of satellite measurements (infrared, microwave) and in-situ data. Represents the foundation temperature below the daily warm surface layer. (Satellite and in-situ analysis) - Place search
- Natural Earth (public domain) · GeoNames (CC BY 4.0) / OpenStreetMap (ODbL)