Forest Grove (OR) Rainfall & Precipitation: Monthly Averages and Year-Round Insights

This page shows the average amount of rainfall per month in Forest Grove (OR). 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.

Forest Grove has a notably wet climate with abundant precipitation, recording 1111 mm of rain/snowfall per year.

Monthly Precipitation Levels

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

The climate in Forest Grove shows significant variation throughout the year. Expect 216 mm of precipitation during the wettest month December, distributed over 21 rainy days.

In contrast, July offers drier and sunnier days, with around 8 mm of rainfall over 3 rainy days.

December, the city’s wettest month, has a maximum daytime temperature of 7°C. During the driest month July you can expect a temperature of 27°C. For more detailed insights into the city’s temperatures, visit our Forest Grove 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

Forest Grove’s average annual precipitation is 1111 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.

In Seoul, South Korea, the average annual precipitation is 1237 mm, with most rain falling during the summer monsoon season.

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

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

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 Forest Grove (OR)’s weather, including sunshine hours, humidity levels, and temperature data, visit our Forest Grove (OR) Climate page.