Have you wondered how much rain or snow has fallen? Have you noticed that what was reported at the official National Weather Service Cooperative site does not match what you observed at your location? There is a volunteer organization that is working to answer both questions: CoCoRaHS.
What is CoCoRaHS?
CoCoRaHS is an acronym for the Community Collaborative Rain, Hail and Snow Network. CoCoRaHS is a unique, non-profit, community-based network of volunteers of all ages and backgrounds working together to measure and map precipitation (rain, hail, and snow). By using low-cost measurement tools, stressing training and education, and utilizing an interactive website, the aim is to provide the highest quality data for natural resource, education, and research applications. CoCoRaHS has been active in Kansas since 2004. More observers are always very welcome.
Each time a rain, hail, or snow storm crosses your area, volunteers take measurements of precipitation from as many locations as possible. These precipitation reports are recorded on the website, https://cocorahs.org/. The data are then displayed and organized for the end users to analyze and apply to daily situations ranging from water resource analysis and severe storm warnings to neighbors comparing how much rain fell in their backyards. For example, Manhattan was able to document the highest rainfall amount during the Labor Day flood, thanks to a CoCoRaHS observer (Figure 1).
Volunteers also report when it DOESN’T rain. Documenting the fact that a part of the county missed out on a precipitation event helps improve understanding of drought conditions. That information is also useful in improving radar and satellite rainfall estimates.
CoCoRaHS is used by a wide variety of organizations and individuals. The National Weather Service, other meteorologists, hydrologists, emergency managers, city utilities (water supply, water conservation, storm water), insurance adjusters, USDA, engineers, mosquito control, ranchers and farmers, outdoor & recreation interests, teachers, students, and neighbors in the community are just some examples of those who visit the website and use the data.
One of the neat things about participating in this network is coming away with the feeling that you have made an important contribution that helps others. By providing your daily observation, you help to fill in a piece of the weather puzzle that affects many across your area in one way or another.
March is the month during which the program focuses on recruiting new observers, but you are welcome to join at any time. To join CoCoRaHS, just go to the website CoCoRaHS.org and click “Join Now”.
If you have questions about the program, contact Mary Knapp at Kansas State University by email at mknapp@ksu.edu or phone at 785-532-7019.
Mary Knapp, Weather Data Library
mknapp@ksu.edu