Grand Junction (CO) Rainfall & Precipitation: Monthly Averages and Year-Round Insights

This page shows the average amount of rainfall per month in Grand Junction (CO). The numbers are calculated over a 30-year period to provide a reliable average. Let's now guide you through the details for a complete overview.

Grand Junction typically sees modest rain/snowfall throughout the year, with an average annual precipitation of 255 mm.

Monthly Precipitation Levels

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

The climate in Grand Junction shows significant variation throughout the year. Expect 32 mm of precipitation during the wettest month September, distributed over 7 rainy days.

In contrast, June offers drier and sunnier days, with around 12 mm of rainfall over 3 rainy days.

September, the city’s wettest month, has a maximum daytime temperature of 28°C and receives 293 hours of sunshine. During the driest month June you can expect a temperature of 32°C. For more detailed insights into the city’s temperatures, visit our Grand Junction 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

Grand Junction’s average annual precipitation is 255 mm. Let’s compare this to some popular worldwide tourist destinations:

The city of Rome, Italy, has an average annual precipitation of 832 mm, spread fairly evenly throughout the year.

Meanwhile, Buenos Aires, Argentina, enjoys a humid subtropical climate with 1000 mm of annual rainfall, mostly in the summer.

In Brisbane, Australia, the annual precipitation is 979 mm, making it wetter than Sydney.

Mumbai, India, experiences a tropical monsoon climate with 1860 mm of annual rainfall, with the majority of precipitation happening during the monsoon season from June to September.

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.

Interesting weather facts

• Mawsynram in India is noted as being the wettest place on earth, with over 11 meters of rain falling every year.
• In contrast, Antofagasta in Chile is among the driest places on the planet, getting less than 0.1mm per year, with some years recording virtually no rainfall.
• Nearly 1,650 thunderstorm cells are estimated over the planet at any given time.

For more detailed information about Grand Junction (CO)’s weather, including sunshine hours, humidity levels, and temperature data, visit our Grand Junction (CO) Climate page.