Rancho Cucamonga (CA) Rainfall & Precipitation: Monthly Averages and Year-Round Insights

This page shows the average amount of rainfall per month in Rancho Cucamonga (CA). The numbers are calculated over a 30-year period to provide a reliable average. Now, let’s explore all the details to give you a full picture.

With annual rainfall averaging 318 mm, Rancho Cucamonga maintains relatively low precipitation levels throughout the seasons.

Monthly Precipitation Levels

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

Rancho Cucamonga can be quite wet during December, receiving approximately 98 mm of precipitation over 8 rainy days.

In contrast June, experiences much drier conditions, with 0.2 mm of rainfall, spread across 0 rainy days.

December, the city’s wettest month, has a maximum daytime temperature of 18°C and receives 205 hours of sunshine. During the driest month June you can expect a temperature of 30°C. For more detailed insights into the city’s temperatures, visit our Rancho Cucamonga Temperature page.

Annual Precipitation in the United States of America

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

Amsterdam Precipitation Compared World Wide

Rancho Cucamonga’s average annual precipitation is 318 mm. Let’s compare this to some popular worldwide tourist destinations:

Boston, USA, experiences 1238 mm of annual precipitation, including significant snowfall during the winter.

Beijing, China, receives 560 mm of annual precipitation, concentrated in the summer months.

Perth, Australia, receives 565 mm of rainfall annually, mostly during the winter months.

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 Rancho Cucamonga (CA):

• 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 Rancho Cucamonga (CA)’s weather, including sunshine hours, humidity levels, and temperature data, visit our Rancho Cucamonga (CA) Climate page.