Cambodia in May: Weather, Crowds & What to Expect

Siem Reap & Northwest (Angkor, Battambang)

June brings the monsoon pulse in earnest: regular, heavy afternoon rains and high humidity. The temples are often misty in the mornings and late showers can make the later part of the day cooler; mosquitoes increase, so bring repellent. Tonle Sap’s flood pulse has started in the lowlands - boat-accessible floating villages expand, offering dramatic water-level contrasts for photography.

Tonle Sap & Central Plains (Phnom Penh, Tonle Sap Lake, Kampong Thom)

The arrival of the monsoon in May brings sudden, heavy downpours that rapidly increase humidity; daytime temperatures ease slightly into the high 20s-low 30s. Riverbanks and low-lying roads start to show the first signs of waterlogging; ferry schedules can be interrupted by sudden storms. Travelers should be prepared for wet gear, boots for muddy stretchers, and the reward of fewer tourists at Phnom Penh’s museums.

Southern Coast & Islands (Sihanoukville, Koh Rong, Koh Rong Samloem, Kep)

May marks the monsoon’s onset for the coast: showers increase and seas grow rougher, with more cancelled trips to Koh Rong around stormy weather. Rain usually falls in heavier bursts interspersed with bright periods, and humidity climbs sharply. Many beach resorts reduce services and some island bungalows close for the season; bring a waterproof bag and expect fewer tourists.

Cardamom Mountains & Southwest (Koh Kong, Cardamom range, Bokor, Botum Sakor)

May marks the start of the southwest monsoon influence: heavy showers become more frequent and tracks into the Cardamoms begin to deteriorate. The jungle switches to loud rain rhythms and waterfalls gain volume, but landslides and impassable sections are possible on unpaved roads. If you plan remote treks, use an experienced guide and expect flexibility in scheduling.

Northeast Uplands (Ratanakiri, Mondulkiri - highlands, waterfalls, ethnic villages)

May brings the monsoon and a dramatic change: heavy, regular rains swamp upland trails and rivers swell quickly, making some hikes hazardous. Ratanakiri’s crater lakes and waterfalls start to fill and are particularly impressive after storms, but roads to remote villages can become unreliable. Travel during the rains requires flexible plans, a local guide, and sturdy waterproof gear.