Cambodia weather and when to visitអាកាសធាតុកម្ពុជា

Cambodia sits in the tropical monsoon belt. The southwest monsoon draws moist air off the Gulf of Thailand from roughly May to October, delivering nearly all the country's rain; the northeast monsoon then brings dry, cooler air from November to March. Temperatures vary far less than rainfall does — lowland highs sit in the low thirties Celsius most of the year.

Rain in the wet season is rarely all-day drizzle. The typical pattern is a bright morning followed by an intense downpour in the late afternoon lasting one to two hours, then clearing. September and October are the wettest months and the only period when multi-day rain and localised flooding are common, particularly along the Mekong and around the Tonle Sap.

This is the most comfortable window and the main tourist season. Days are sunny with highs of 28-32°C, humidity drops noticeably, and nights in Phnom Penh and Siem Reap can fall to the low twenties. December and January are the driest and coolest months.

The trade-off is crowds and cost. Angkor's sunrise viewpoints are busy, hotel rates in Siem Reap and along the coast are at their annual peak, and popular tours book out — particularly around Christmas, New Year and the Water Festival in November.

Heat builds through March and peaks in April, when inland highs regularly reach 35-40°C and the humidity climbs ahead of the first rains. Temple visits need an early start and a hard stop by mid-morning; afternoons are best spent indoors or by water.

It is also when Khmer New Year falls, so the country is at its most festive even as it is at its hottest. The coast and the islands are more bearable than Phnom Penh or Siem Reap thanks to sea breezes, and prices for inland accommodation soften.

The green season is the cheapest and quietest time to travel, and visually the best. Rice paddies are vivid, moats and waterfalls are full, and Angkor's temples photograph beautifully with dramatic skies and few visitors. Rain typically confines itself to a heavy afternoon burst.

It is also the only time to see the Tonle Sap at full extent: the lake swells to several times its dry-season area, and the floating villages and flooded forest near Kampong Phluk are genuinely afloat rather than stranded on stilts above dry ground.

The caveats are real, though. Unpaved roads in remote provinces turn to mud, some outlying temples and island boat services become unreliable, and September and October can bring several consecutive wet days. Coastal seas are rougher and some island transfers are cancelled.

For the best all-round weather with an accepted premium in price and crowds, pick December to February. For the best compromise, target the shoulder months of November and early June — decent weather, lower rates, thinner crowds.

If your priority is photography, the Tonle Sap or budget, aim for July to early September. If it is the coast and islands, favour November to April, when seas are calm and ferries run reliably. Our weather page carries current forecasts for Phnom Penh, Siem Reap, Sihanoukville, Battambang and other cities.