Situated in the tropical zone of Southeast Asia, Cambodia experiences a climate dictated by the annual monsoon cycle, which brings about two distinct seasons: dry and wet. The monsoon cycle is influenced by changes in air pressure over central Asia. During the summer months (from June to October), the drop in pressure draws moist air from the ocean inland, resulting in the southwest monsoon rains that characterize Cambodia’s wet season. This period can see rain and high humidity prevail during this time.

From early November, the southwest monsoon retreats from northern Cambodia and dissipates in the central-southern regions by late November. From then until May, Cambodia enjoys a rainless dry season as the rising air pressure over central Asia ushers in cool, dry air across the region. The dry season sees lighter winds and lower humidity, with infrequent precipitation.

Temperatures in Cambodia remain high throughout the year, exceeding 35°C, and sometimes even reaching 40°C, particularly in March and April, the hottest months. Conversely, November, December, and January are relatively cooler, with temperatures averaging around 24°C-26°C.

Annual rainfall varies across the country, with the central lowlands receiving around 1,300 to 1,800 mm of rainfall, while coastal regions may experience over 2,000 mm. Highland areas, such as the Cardamom Mountains, can receive up to 5,000 mm of rain annually.

Typhoons are rare in Cambodia but can bring heavy rains, particularly between late July and September. However, they are usually weakened by the time they reach Cambodia due to their passage over Vietnam.