Koh Rong in August
Last fact-checked: October 2026. Climate figures are long-term averages for nearby Sihanoukville.
August is the wettest month of the year on average. It is the quietest time on the island.
| Average daytime high | 31 °C |
| Average night-time low | 24 °C |
| Average rainfall | 617 mm |
| Average sea temperature | 29.2 °C |
Long-term averages for nearby Sihanoukville: World Meteorological Organization 1982-2024; sea temperature: seatemperature.org.
Weather
Expect a lot of rain, over 600 mm on average, often in long spells, with only short sunny breaks.
Sea and activities
Sea conditions are often rough and ferries can be cancelled. The upside: the waterfalls on Koh Rong are at their best.
Holidays and crowds
Low season with the lowest prices. Stay near a main pier (Koh Touch or Long Set) and plan with flexibility.
Best Beaches & Coast Conditions in August
East Coast bays (Long Set, Pagoda, Coconut Beach) remain sheltered and calmest; avoid swimming in rough surf on the open west coast during monsoon squalls.
- Recommended Activities: Exploring roaring waterfalls, mangrove boardwalks and kayaking, enjoying discounted 4- and 5-star spa resorts, and night plankton swims on calm evenings.
- What to Pack & Booking Tip: Waterproof dry bag, motion-sickness tablets for the 40-minute ferry crossing, umbrella/rain jacket, and downloaded offline maps/movies.
Koh Rong Weather in August: FAQ
How wet is August on Koh Rong?
August is statistically the wettest month of the year (~617 mm), with a mix of sunny mornings, dramatic monsoon cloudbursts, and occasional 2-day rainy spells.
What if ferries are cancelled due to weather in August?
Port authorities occasionally pause afternoon speedboats during high winds; morning ferries (08:00–10:00) are the most reliable, and you should never schedule a flight on the same day as your ferry back.
Are restaurants and resorts open in August?
Yes, Koh Touch, Long Set, and major resorts remain open year-round thanks to grid power and concrete roads.