Colorado State’s Popular Rain and Hail Study Program is Looking for Weather-Loving Volunteers at the Colorado Farm Show

Representatives from Colorado State University’s Community Collaborative Rain and Hail Study, or CoCoRaHS, will be showing Colorado’s agricultural community how to use valuable data from the statewide weather observing network at the 39th Annual Colorado Farm Show Jan. 28-30 at the Island Grove Regional Park in Greeley. CoCoRaHS staff will also be on hand to recruit volunteer weather watchers to help study Colorado’s complex patterns of precipitation.

Scientists from the CSU-CHILL weather radar facility and the National Weather Service also will join CoCoRaHS representatives to discuss how their collaborative efforts benefit the state’s farm and ranch industries.

CoCoRaHS is a science education, research and outreach project housed in Colorado State’s Colorado Climate Center. Through CoCoRaHS, the size, intensity, duration and patterns of rain, hail and snow storms are analyzed and documented by more than 450 volunteers in communities throughout the state. The data gathered by volunteers provides important daily decision-making information for agriculture, industry, home water use, utility providers, insurance companies, resource managers and educators.

"This is a community project that benefits the entire state, and anyone can help. The only requirements are enthusiasm for watching and reporting weather conditions and the desire to learn about the power and beauty of our natural world," said Nolan Doesken, research climatologist at the Climate Center and director of CoCoRaHS. "CoCoRaHS volunteers are learning about weather while providing valuable information to local and state organizations as well as individuals."

Each morning, CoCoRaHS volunteers take measurements of precipitation using backyard gauges provided by the Climate Center. Precipitation reports are transmitted daily via telephone or the Internet to the Climate Center and are made available on the Center’s Web site at Climate analysts then process the data and prepare detailed maps showing rain, hail and snow patterns.

"For all of our modern technology, there is still nothing better than a simple backyard rain gauge and someone who is excited to measure it," Doesken said. "Rain is so variable and it affects so much of what we do that it just makes sense to measure it as accurately as we can."

Thanks to a recent National Science Foundation grant to enhance the program, CoCoRaHS is looking to recruit more volunteers at the Colorado Farm Show to help expand the program’s region of coverage into far eastern Colorado, southeastern Wyoming, western Nebraska and western Kansas.

"Without accurate data, poor decisions regarding the efficient uses of water, pesticides and other resources could be made," said Doesken. "The research data gathered by CoCoRaHS’s volunteers provides widespread information that leads to appropriate, well-informed decisions that could not otherwise be made regarding Colorado’s climate and water use."

This type of accurate information is helping several organizations.The National Weather Service, one of the largest users of the volunteer program’s data, monitors CoCoRaHS rain and hail data daily to help track severe weather, issue severe storm warnings and verify forecasts. Outside of work, about one-third of local National Weather Service employees volunteer for CoCoRaHS.

The U.S. Department of Agriculture uses CoCoRaHS information to evaluate drought, hail and crop conditions and to improve estimates of future crop yields. The U.S. Bureau of Reclamation and the Northern Colorado Conservancy District both use CoCoRaHS data to look at how precipitation affects water inputs into specific river basins and how it impacts irrigation demands in those areas. Colorado State’s CSU-CHILL Radar research laboratory uses CoCoRaHS hail reports to test and improve new methods for remotely tracking hail storms and flash flood events using advanced weather radar technology.

Additionally, teachers from throughout the state can use CoCoRaHS information to help teach math and science to students. Lesson plans are provided via the Web for free to all teachers who want to use the project in their classrooms.

To learn more about the project or to sign up to become a CoCoRaHS volunteer, go to the CoCoRaHS Web site at To learn more about the Colorado Farm Show, visit the Web at