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Join CoCoRaHS - a Nationwide Precipitation Network!


It's time to think about spring flowers and summer showers. You are invited to join a volunteer nationwide precipitation observing network. As part of the network, you will report rain, snow and even hail. Your precipitation observations contribute to CoCoRaHS, the Community Collaborative Rain, Hail and Snow Network.

Weather buffs of all ages and backgrounds can join this rapidly growing network of volunteer weather observers. By joining and participating, you will play an active role in meteorological reporting and research using inexpensive equipment (a rain gage) in your backyard. No experience is necessary, just the enthusiasm to report your observation each morning through the CoCoRaHS web page.

CoCoRaHS was launched in Colorado in 1998 following a devastating flash flood in Fort Collins. A dense precipitation network can increase the detection of a developing flash flood. CoCoRaHS now boasts over 12,000 volunteer observers nationwide and in Canada participating.

All correspondence, data collection and training will be done on-line through the CoCoRaHS web site - If you have questions, you can email your regional coordinator. Tables and maps of the precipitation in each state are available for all to view online.

The only equipment needed is a 4" cylindrical rain gauge available from the network. In order for reports to be consistent, the use of a 4" rain gage is mandatory. A gage can be purchased for about $30 (plus shipping) through the web site. Many commercial weather supply companies also sell the 4" rain gages. A yardstick should be used to measure snow depth.

Consider joining CoCoRaHS - sign up today!


Click here to visit the CoCoRaHS web site for more information.


Click here to sign up to be a CoCoRaHS observer.


Click here to view the CoCoRaHS page for Ohio.


Click here to view the CoCoRaHS page for Pennsylvania.


"CoCoRaHS - Because Every Drop Counts!"