CoCoRaHS Observation Network

CoCoRaHS Observations and Information

In addition to daily precipitation reports, you can also report on the local conditions in your area!

In addition to your daily precipitation measurements, you can also submit weekly reports describing recent weather conditions and their impacts on the local environment in your community. The focus on regular reporting is intended to create a comparison of change over time. On the Condition Monitoring Report Form, you’ll select from one of seven categories indicating how wet or dry conditions are in your area and provide a brief description of local conditions. Learn more on the Condition Monitoring Resources Page. Here you’ll find a training slideshow and animation as well as a list of frequently asked questions.

What is CoCoRaHS?

CoCoRaHS stands for the Community Collaborative Rain, Hail & Snow network. It is a unique, non-profit, community-based network of volunteers of all ages and backgrounds working together to measure and map precipitation (rain, snow and hail). The network originated with the Colorado Climate Center at Colorado State University in 1998 thanks in part to a devastating flood that occurred in the previous year.

It is exciting to see how CoCoRaHS has expanded across the United States at a rapid pace over the past few years and is now the largest provider of daily precipitation observations in the country. However, CoCoRaHS has expanded beyond the United States and is now receiving observations from Canada, Puerto Rico, U.S. Virgin Islands, and the Bahamas!

So when you have the chance please tell a friend or neighbor about this exciting grassroots effort to measure precipitation in the backyards of citizens from the Atlantic to the Pacific...and beyond. It's easy to join, takes only five minutes a day and is a fun way to learn about this wonderful natural resource that falls from the sky.

Can I participate?

Absolutely! The ultimate goal of the program is to have one observer per square mile in urban/suburban areas and one observer every 36 square miles in rural areas. Everyone can help, young, old, and in-between. The only requirements are an enthusiasm for watching and reporting weather conditions and a desire to learn more about how weather can effect and impact our lives.

Once trained, volunteers collect data using low cost measuring tools such as a 4-inch diameter high capacity rain gauge (pictured right), snow boards to measure snow, and aluminum foil-wrapped Styrofoam hail pads in some states. Information on purchasing a rain gauge can be found via the CoCoRaHS main page.

Is training available?

Free training sessions are held around the state at various times of the year. Attending one of these personalized sessions is highly recommended. However, there are also training materials available online. For more information on training options check out the Illinois CoCoRaHS page.

How do I join?

Either click on the “Join CoCoRaHS” image to the left or visit the CoCoRaHS home page at www.cocorahs.org to get more information on the program.