Phnom Penh Rainfall & Precipitation: Monthly Averages and Year-Round Insights

This page shows both the average monthly rainfall and the number of rainy days in Phnom Penh, Phnom Penh Municipality, Cambodia. Long-term data from 1990 to 2020 was used to calculate these averages. Let’s explore the details to provide you with a complete overview.

Phnom Penh experiences significant rainfall throughout the year, averaging 1415 mm of precipitation annually.

Monthly Precipitation Levels

The average number of days each month with precipitation (> 0.2 mm)

Significant seasonal changes in precipitation occur throughout the year. During the wet season, September receives substantial rainfall, averaging 252 mm of precipitation, recorded across 19 rainy days.

In contrast, the drier season, February brings less rainfall, with 12 mm over 2 rainy days.

September, the wettest month, has a maximum daytime temperature of 33°C. The city receives 129 hours of sunshine in this period. During the driest month February you can expect a temperature of 35°C. For more detailed insights into the city’s temperatures, visit our Phnom Penh Temperature page.

Annual Precipitation in Cambodia

The map below shows the annual precipitation across Cambodia. You can also select the different months in case you are interested in a specific month.

Amsterdam Precipitation Compared World Wide

Phnom Penh’s average annual precipitation is 1415 mm. Let’s compare this to some popular worldwide tourist destinations:

Chicago, USA, sees an annual precipitation of 1062 mm, with rain and snow contributing to its humid climate.

In Seoul, South Korea, the average annual precipitation is 1237 mm, with most rain falling during the summer monsoon season.

Adelaide, Australia, enjoys 511 mm of annual precipitation, with dry summers and wet winters.

Bangkok, Thailand, experiences a tropical monsoon climate with 1668 mm of annual rainfall, with the heaviest precipitation occurring during September and October.

How is Precipitation Measured?

Precipitation amounts are measured using specific gauges installed at weather stations, collecting both rain and snow and any other type of precipitation. Rainfall is measured directly in millimeters, while that from snow and ice is obtained by melting it. Automated systems often incorporate heaters to make this easier.

Information from these stations is transmitted via Wi-Fi, satellite, GPS, or telephone connections to central monitoring networks. This information is immediately updated and integrated into weather models and forecasts.

Global Warming and Precipitation

Climate change is affecting precipitation patterns worldwide, including Phnom Penh:

• Changing Rainfall Patterns: Global warming causes drastic changes in the patterns of rainfall. Some areas have been experiencing increased frequency and intensity of rainfall, while other areas experience longer dry spells or even droughts.
• Local Impacts: Many regions are experiencing heavier rainfall in the winter months and drier, hotter summers. This affects agriculture, water resources, and ecosystems.

For more detailed information about Phnom Penh’s weather, including sunshine hours, humidity levels, and temperature data, visit our Phnom Penh Climate page.