Great Falls (MT) Rainfall & Precipitation: Monthly Averages and Year-Round Insights

This page shows the average amount of rainfall per month in Great Falls (MT). The numbers are calculated over a 30-year period to provide a reliable average. Now, let’s break down all the details for a clearer picture.

Great Falls maintains relatively dry conditions year-round, recording average annual precipitation of 387 mm.

Monthly Precipitation Levels

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

Great Falls can be quite wet during May, receiving approximately 67 mm of precipitation over 12 rainy days.

In contrast March, experiences much drier conditions, with 15 mm of snow/rainfall, spread across 7 snowy/rainy days.

May, the city’s wettest month, has a maximum daytime temperature of 18°C and receives 289 hours of sunshine. During the driest month March you can expect a temperature of 9°C. For more detailed insights into the city’s temperatures, visit our Great Falls 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

Great Falls’s average annual precipitation is 387 mm. Let’s compare this to some popular worldwide tourist destinations:

The climate in San Francisco, USA, is influenced by coastal weather, with 469 mm of rainfall mostly during the winter months.

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

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.

Interesting weather facts

• "Ginger" was the longest-lasting Atlantic tropical storm, which spun around the open ocean for 28 days in 1971.
• The world's largest snowflake was recorded in the Guinness Book of Records, at 38 cm wide and 20 cm thick. The snowflake fell at Fort Keogh, Montana, USA, on 28 January 1887.
• The greatest snowfall recorded was on Mt. Rainier, Washington State, USA—over 31.5 meters fell during the winter of 1972.

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