Collinsville (IL) Rainfall & Precipitation: Monthly Averages and Year-Round Insights

This page shows the average amount of rainfall per month in Collinsville (IL). 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.

Collinsville has a relatively rain/snowy climate with high precipitation levels, averaging 1148 mm of rain/snowfall annually.

Monthly Precipitation Levels

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

Significant seasonal changes in precipitation occur throughout the year. During the wet season, June receives substantial rainfall, averaging 138 mm of precipitation, recorded across 12 rainy days.

In contrast, the drier season, January brings less snow/rainfall, with 53 mm over 8 snowy/rainy days.

June, the city’s wettest month, has a maximum daytime temperature of 30°C and receives 293 hours of sunshine. During the driest month January you can expect a temperature of 5°C. For more detailed insights into the city’s temperatures, visit our Collinsville 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

Collinsville’s average annual precipitation is 1148 mm. Let’s compare this to some popular worldwide tourist destinations:

In Barcelona, Spain, the average annual precipitation is 620 mm, evenly distributed across the year with no extreme wet or dry seasons.

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

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

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 Collinsville (IL):

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