Koh Samui Climate: Sunshine Hours, Temperature & Best Time to Visit

Koh Samui climate month by month: sunshine hours, temperature, rain and day length from weather station data 1991–2020. Best time to visit: February, March, April. Sunniest month: March.

  • 2,342 hours of sunshine a year – 1.4 times as much as London. Warmest is May at 31 °C by day.
  • Best time to visit: February, March, April

Sunshine and temperature in Koh Samui month by month

  • January: 6.5 h Sun/day (200 h), Daytime high 28 °C, Night 25 °C, Rain 135 mm, Holiday score 68
  • February: 7.9 h Sun/day (223 h), Daytime high 28 °C, Night 26 °C, Rain 38 mm, Holiday score 83
  • March: 8.1 h Sun/day (252 h), Daytime high 30 °C, Night 26 °C, Rain 114 mm, Holiday score 77
  • April: 7.8 h Sun/day (235 h), Daytime high 31 °C, Night 27 °C, Rain 90 mm, Holiday score 75
  • May: 6.7 h Sun/day (208 h), Daytime high 31 °C, Night 28 °C, Rain 170 mm, Holiday score 64
  • June: 6.3 h Sun/day (188 h), Daytime high 30 °C, Night 27 °C, Rain 167 mm, Holiday score 66
  • July: 6.3 h Sun/day (194 h), Daytime high 30 °C, Night 27 °C, Rain 166 mm, Holiday score 66
  • August: 6.2 h Sun/day (191 h), Daytime high 29 °C, Night 27 °C, Rain 144 mm, Holiday score 66
  • September: 6.0 h Sun/day (181 h), Daytime high 29 °C, Night 27 °C, Rain 181 mm, Holiday score 65
  • October: 5.2 h Sun/day (161 h), Daytime high 29 °C, Night 27 °C, Rain 246 mm, Holiday score 61
  • November: 4.9 h Sun/day (146 h), Daytime high 29 °C, Night 27 °C, Rain 375 mm, Holiday score 60
  • December: 5.3 h Sun/day (163 h), Daytime high 29 °C, Night 26 °C, Rain 262 mm, Holiday score 62
  • Temperature: NASA POWER model value (grid, ±2–3 °C) · Sunshine: estimated from NASA satellite data (±15 %) · Rain: NASA POWER model value (grid, ±2–3 °C). Averages 1991–2020, source: Deutscher Wetterdienst (CLIMAT station data, CC BY 4.0) and NASA POWER; single years differ.

Questions

  • When is the best time to visit Koh Samui? By sunshine, warmth and rain the best months are February, March, April. Sunniest is March with 252 hours of sunshine, warmest May at 31 °C.
  • How many hours of sunshine does Koh Samui get a year? About 2,342 hours – 1.4 times as many as London (1,675 hours).
  • When does it rain most in Koh Samui? In November, with 375 mm on average. The driest month is February.
  • How warm is Koh Samui in January and July? In January the average daytime high is 28 °C, in July 30 °C.