The region is best visited from November to February during the cool dry season. Perfect temperatures for Phnom Penh: 22-30°C, low humidity (50-65%), clear skies. It's the optimal window for sunset cruises on the Mekong, outdoor visits, and traditional festivals — notably Bon Om Touk (Water Festival, November, pirogue races on the Tonle Sap and Phnom Penh river, up to 2 million people mobilised in the capital).
The hot season (March to May) is gruelling in Phnom Penh: 35-38°C felt 40+°C with humidity, severe air pollution. Outdoor visits must be condensed on mornings and late afternoons. The wet season (June to October) brings daily late-afternoon rain. Phnom Penh suffers from regular urban flooding in September-October — limited rainwater drainage system, some downtown streets temporarily impassable, traffic can be paralysed during and after downpours.
Our advice: aim for November to February for Phnom Penh, or March as a compromise. Avoid September-October (urban flooding).
Read also
- Phnom Penh — The capital: Royal Palace, S-21, Killing Fields, Mekong riverside.
- Cambodia — Complete country guide: visa, currency, regions, best time to visit.
- Siem Reap and Angkor — The Angkor archaeological site (UNESCO) — to combine with Phnom Penh in 8-10 days.
- Cambodian south coast — Kampot, Kep, Koh Rong islands: the beach dimension — accessible from Phnom Penh.