Koh Rong in September
Not the best time
The wettest month where Koh Rong becomes a serious commitment rather than a casual beach getaway. Only attempt if you genuinely enjoy tropical storms and extreme solitude.
Weather
September often brings the wettest conditions of the year with near-daily heavy rainfall and occasional all-day storms. Humidity stays brutally high and sunshine becomes a precious commodity. When it does clear up, the island looks incredibly lush and green.
30°C high25°C low20 rain days
Crowds & Cost
low crowds
~$40/day average
Events & Festivals
- •Pchum Ben (Ancestor Festival)
September Tips
- •Many restaurants and tour operators close for the month
- •Bring books, cards, or offline entertainment
- •Pchum Ben means local boat schedules are very limited
All Months
November through April is peak season for good reason. The northeast monsoon keeps things dry, temperatures hover around 28°C, and the sea stays calm for boat transfers. December and January are busiest — book accommodation well ahead.
May through October brings the southwest monsoon. Expect daily afternoon downpours, rough seas that cancel boat services, and many guesthouses closing entirely. But here's the upside: the few places that stay open offer serious discounts, and you'll have beaches almost entirely to yourself between rain showers.
The bioluminescent plankton peaks during the dry season, especially on dark nights between November and March. Full moon periods wash out the effect, so time your visit for the new moon if this is your main reason for coming.
Avoid Cambodian holidays like Khmer New Year (April) and Pchum Ben (October) when domestic tourists pack the island. Chinese New Year (January/February) also brings crowds, though the atmosphere stays more international than local holiday periods.
Koh Rong Scores
Solo
7/10
Couples
7/10
Families
5/10
Adventure
8/10
Budget
8/10
Luxury
3/10