Cayenne Rainfall & Precipitation: Monthly Averages and Year-Round Insights

This page shows both the average monthly rainfall and the number of rainy days in Cayenne, French Guiana. These averages rely on historical data collected over 30 years, from 1990 to 2020. Let's now guide you through the details for a complete overview.

Cayenne has a relatively rainy climate with high precipitation levels, averaging 2663 mm of rainfall annually.

Monthly Precipitation Levels

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

The seasons in Cayenne, bring significant changes in precipitation. The wettest month, May, receives heavy rainfall, with an average of 403 mm of precipitation.

This rainfall is distributed across 26 rainy days. In contrast, the driest month, September, experiences much less rainfall, totaling 65 mm over 5 rainy days. These distinct seasonal differences provide diverse experiences throughout the year.

May, the wettest month, has a maximum daytime temperature of 30°C. The city receives 122 hours of sunshine in this period. During the driest month September you can expect a temperature of 32°C. For more detailed insights into the city’s temperatures, visit our Cayenne Temperature page.

Annual Precipitation in French Guiana

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

Amsterdam Precipitation Compared World Wide

Cayenne’s average annual precipitation is 2663 mm. Let’s compare this to some popular worldwide tourist destinations:

In Lisbon, Portugal, the average annual precipitation is 774 mm, characterized by wet winters and dry summers typical of the Mediterranean climate.

Osaka, Japan, experiences 1507 mm of rainfall annually, spread across the year with wetter summers.

In Tokyo, Japan, the average annual precipitation is 1528 mm, with significant summer rains due to typhoon season.

Singapore, situated near the equator, gets 2581 mm of rainfall annually, with no distinct dry season and consistent monthly precipitation.

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 Cayenne:

• 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 Cayenne’s weather, including sunshine hours, humidity levels, and temperature data, visit our Cayenne Climate page.