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Do you enjoy recording weather conditions in your own backyard? Do you like to keep track of how much rain or snow fell at your location? If so, consider joining the CoCoRaHS network.

CoCoRaHS Rain Gauge

Every morning, CoCoRaHS observers record important measurements of how much rain, hail, or snow fell at their location during the previous 24 hours and send that information out via the CoCoRaHS web page or mobile app.

Volunteers of all ages and backgrounds (citizen scientists) are measuring precipitation in their own backyards as part of CoCoRaHS - the Community Collaborative Rain, Hail and Snow Network which has grown to over 20,000 volunteer observers covering every state of the country. It's fun, easy and takes less than five minutes a day. 

"We are pleased that this simple backyard monitoring program has become so popular," said Nolan Doesken, the Colorado State Climatologist at the Colorado Climate Center in Fort Collins, Colorado. "These volunteers are providing scientists around the country with excellent precipitation and hail monitoring statistics for tracking weather patterns and water supplies."

The CoCoRaHS network engages volunteers of all ages from grade schoolers on up to folks in their 90's to document the size, intensity, duration and patterns of precipitation by taking simple measurements in their own backyards. Volunteers only need a cylindrical rain gauge, some training and an interest in weather to participate in the program. The specific rain gauge that CoCoRaHS uses are available from distributors on the network's website ( for about $40 plus shipping.
CoCoRaHS Logo
Data from CoCoRaHS volunteers are now being routinely viewed and used by many professions and organizations including the National Weather Service, meteorologists, hydrologists, emergency managers, city utilities, insurance adjusters, agribusinesses, engineers, science teachers and many more.  Data are used for many applications such as water resource planning, severe storm warnings, teaching earth science, predicting crop yields and for assessing hail damage.


How much does it cost?

Joining the CoCoRaHS program is free, however all observers are required to purchase and install an official CoCoRaHS rain gauge to ensure accuracy and consistency from all observations. Cost of the rain gauge is approximately $40 plus shipping and can be purchased from a link on the CoCoRaHS web site.

Sign up Today! Click here to go to the CoCoRaHS online application form. Remember, observers are required to purchase an official CoCoRaHS rain gauge (approximately $45) and view online training slides.

All additional new CoCoRaHS observers are welcome in Illinois, Indiana, Kentucky, and Missouri!

Training slides are available online here.

View CoCoRaHS videos to learn more.