Like most of Southeast Asia, Cambodia is hot and humid year round. December-February (the high season for tourism) is the coolest time of year, though temperatures are still in the 80s throughout most of the country. March-June is the hottest period, when the mercury regularly climbs above 100, and humidity is high as well. The rainy season runs from June to November, though it sometimes rains during other months. All in all, unless you’re coming from another tropical climate, Cambodia will feel hot and steamy any time of year.