Warm
Average highs sit around 30°C, giving warm days by monthly-average standards.
October verdict
Mixed for holiday weather
Average highs sit around 30°C, giving warm days by monthly-average standards. Sunshine averages 5.7h per day, enough for a balanced month. Rainfall averages 275mm, so showers are a real planning factor.

Monthly averages
Temp
30°C
Rain
275mm
Sun
5.7h
Sea
29°C
Weather score
52
Mixed
Warm
Average highs sit around 30°C, giving warm days by monthly-average standards.
Wet
Rainfall averages 275mm, so showers are a real planning factor.
Some sun
Sunshine averages 5.7h per day, enough for a balanced month.
Warm sea
Sea temperatures average 29°C, so swimming is usually comfortable by monthly-average standards.
Map
Compare Koh Samui, Thailand with nearby places by weather score, rain, sun, temperature, and swim conditions.
October30°C average high
October is close to Koh Samui's yearly temperature average, giving a typical read on daytime heat.
Warmest monthsApril to September
This stretch sets the upper range for average daytime heat.
October275mm average rain
October sits near Koh Samui's yearly rainfall average, so rain is a normal planning factor rather than an outlier.
Driest monthsJanuary to September
This is the drier part of the year, when outdoor plans usually need less weather flexibility.
October5.7 hours average sun
October is one of Koh Samui's cloudier months, so sunshine-led plans are less reliable.
Brightest monthsFebruary to April
This stretch has the strongest sunshine in the monthly averages.
October29°C average sea
October is close to Koh Samui's yearly sea-temperature average, so swimming comfort is fairly typical.
Warmest seaApril to September
Sea temperatures are usually near 30°C in this stretch, so swimming comfort is at its strongest.
October52 weather score
October is one of the weakest weather-score months, when the overall mix is less favourable than the rest of the year.
Best weather monthsFebruary to March
These months have the strongest weather score in the monthly averages.