Grand Junction (CO) Monthly Rainfall & Precipitation

This page shows both the average monthly rainfall and the number of rainy days in Grand Junction, Colorado, United States of America. These averages rely on historical data collected over 30 years, from 1990 to 2020. Now, let's explore all the details to give you a full picture.

Grand Junction experiences desert-like conditions in terms of precipitation with almost no rain/snowfall, generally receiving 245 mm (9.6 in) annually.

Monthly Precipitation Levels

The average number of days each month with precipitation (> 0.2 mm (0.01 in))

The climate in Grand Junction shows significant variation throughout the year. Expect 30 mm (1.2 in) of precipitation during the wettest month October, distributed over 8 rainy days.

In contrast, June offers drier and sunnier days, with around 11 mm (0.4 in) of rainfall over 3 rainy days.

October, the wettest month, has a maximum daytime temperature of 19°C (66°F). The city receives 256 hours of sunshine in this period. During the driest month June you can expect a temperature of 32°C (90°F). For more detailed insights into the city's temperatures, visit our Grand Junction Temperature page.

Grand Junction's average annual precipitation is 245 mm (9.6 in). Let's compare this to some popular worldwide tourist destinations:

In Lisbon, Portugal, the average annual precipitation is 774 mm (30 in), characterized by wet winters and dry summers typical of the Mediterranean climate.

Osaka, Japan, experiences 1507 mm (59 in) of rainfall annually, spread across the year with wetter summers.

In Tokyo, Japan, the average annual precipitation is 1528 mm (60 in), with significant summer rains due to typhoon season.

Kuala Lumpur, Malaysia, receives 2529 mm (100 in) of annual rainfall, characteristic of its equatorial tropical rainforest climate, with consistent rainfall throughout the year and peak months during March and November.

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.

The proximity of a location to a large body of water can significantly affect its rainfall patterns:

• Ocean Influence: Coastal regions typically receive more rainfall due to the presence of moisture-laden winds from the ocean. These regions tend to have more humid climates and experience more frequent precipitation, especially in winter.
• Continental Climates: Areas further from the sea, such as inland or continental regions, experience less frequent rainfall and more extreme seasonal variations in precipitation.

• The U.S. has a significant number of thunderstorms every year, with over 14.6 million taking place across the world annually.
• Approximately 70% of lightning bolts strike land rather than oceans.
• A storm named John was the longest-lasting Pacific tropical storm, continuing for 31 days. As it crossed the dateline twice, it changed status from a hurricane to a typhoon and back to a hurricane.

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.