Temperatures in May
It's hot in May in Koh Samui with an average temperature of 34°C. Temperatures this month range from a low of 33°C to a high of 35°C. At night, you can expect temperatures between 27°C and 28°C.
Max and Min Temperatures per Day
This chart shows the daily maximum and minimum temperatures in degrees Celsius for Koh Samui in May. The red line indicates the max temperatures, and the blue line shows the minimums.
Start of May
The month of May starts in Koh Samui with hot temperatures, averaging around 34°C during the day and nights close to 28°C. Plenty of days with a chance of precipitation. Breezy clothes like shorts or a dress, plus a hat and sunglasses, are ideal.
Mid-May
By mid-May, the average daytime temperature rises to around 35°C, with nights close to 28°C. During this part of the month, you can expect regular precipitation, but there’ll also be some sunny days. Breezy clothes like shorts or a dress, plus a hat and sunglasses, are ideal.
End of May
By the end of May, the average daytime temperature in Koh Samui will be around 34°C, with nights close to 28°C. There’s regular precipitation, but with a bit of luck, you’ll also get some dry and sunny days. Breezy clothes like shorts or a dress, plus a hat and sunglasses, are ideal.
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Precipitation in May
In May, there is an average of 162 mm of precipitation, spread over 17 days. The wind speed is around 4 Bft, mostly coming from the Southwest.
Across the whole month, the average precipitation chance is 55% per day. Though that seems frequent, the weather’s variable. There are also a few days with lower precipitation chances.
Precipitation Chance
This chart shows the daily precipitation chance (in percentages) in May for Koh Samui. 0% means it never rained on that day in the past 10 years, and 100% means it rained every day. All values in between represent the average chance of precipitation on that day.
Koh Samui in May |
UK | ||
|---|---|---|---|
 Average Temperature |
34°C | 18°C | |
 High Temp |
35°C | 21°C | |
| Low Temp |
33°C | 15°C | |
 Total Precipitation |
162 mm | 46 mm | |
| Rainy Days |
17 days | 8 days | |
April
UV index
The UV index is a maximum of 9 this month. That's a very high value on the intensity scale of 1 to 11. Unprotected skin can burn within 10-15 minutes.
Is May a good time to visit Koh Samui?
After some sun? Then May isn’t the best time to be in Koh Samui. The temperature is pleasant, but there’s too much chance of rain this month.
The typhoon season in Koh Samui runs from June to November.
Temperature records for Koh Samui in May
With 37°C, Koh Samui hit the highest temperature in the last 10 years in May 2023. The lowest daytime temperature in this month was 28°C in 2022. The extreme night temperatures ranged from a low of 23°C to a high of 30°C.
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Daily Temperature in May in Koh Samui
This chart shows the average daily temperatures, both day and night, for each day in May in Koh Samui, measured in degrees Celsius. The red line represents the maximum temperatures, while the blue line shows the minimums. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, gives an overview of the average daily temperatures during this month.
Daily Precipitation in May in Koh Samui
The chart below shows the average daily precipitation in May for Koh Samui, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are shown at the bottom of the chart.
A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that rain is more likely. But it’s still an average, so each day can be different. Based on historical weather data for May, you can expect around 17 days of rain in Koh Samui.
Daily UV Index in May in Koh Samui
This chart shows the average daily UV index in May in Koh Samui, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Temperature in May in Koh Samui Over the Years
This chart shows the average temperature in May in Koh Samui, measured in degrees Celsius, over the past years.
Total Precipitation in May in Koh Samui Over the Years
This chart shows the average precipitation in May in Koh Samui, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail.
Daily climate in May for Koh Samui
Click on a specific day in May for detailed info on the typical weather on that day in Koh Samui. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in May in Koh Samui
The weather in May in Koh Samui is rated 0 out of 5 stars by 1 visitor. Have you been to Koh Samui? Share your weather experience to help other visitors.
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Average Weather in Koh Samui by Month
Click on a month below to see detailed weather info for Koh Samui. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
Or check out the climate of Koh Samui for all months at once
