The Community Collaborative Rain, Hail, and Snow network, or CoCoRaHS, is looking for volunteers across North Carolina.
The grassroots effort is part of a growing national network of home-based and amateur rain spotters with a goal of providing a high density precipitation network that will supplement existing observations.
CoCoRaHS came about as a result of a devastating flash flood that hit Fort Collins, Colo., in July 1997.
A severe thunderstorm dumped over a foot of rain in several hours while other portions of the city had only modest rainfall. The ensuing flood caught many by surprise and caused $200 million in damages.
CoCoRaHS was born in 1998 with the intent of doing a better job of mapping and reporting intense storms. As more volunteers participated, rain, hail, and snow maps were produced for every storm showing fascinating local patterns that were of great interest to scientists and the public.
North Carolina became the 21st state to establish the CoCoRaHS program in 2007, and by 2010, the CoCoRaHS network had reached all 50 states with 8,000 to 10,000 observations being reported each day. Volunteers document the size, intensity, duration and patterns of rain, hail and snow by taking measurements.
Volunteers can obtain an official rain gauge through the CoCoRaHS website, www.cocorahs.org, for about $25 plus shipping. Besides the need for an official 4 inch plastic rain gauge, volunteers are required to take a training module online and use the CoCoRaHS website to submit their reports.
Observations are immediately available on maps and reports for the public. The process provides accurate measurements to supplement existing networks.
ěNorth Carolina has the most complex climate in the eastern U.S.,î said Ryan Boyles, state climatologist and director of the State Climate Office, based at N.C. State. ěData gathered from CoCoRaHS volunteers can be very important in better understanding our climate.î
ěAn additional benefit of the program to the National Weather Service is the ability to receive timely reports of significant weather (hail, intense rainfall, localized flooding) from CoCoRaHS observers that can assist forecasters in issuing and verifying warnings for severe thunderstorms,î says David Glenn, CoCoRaHS State coordinator and meteorologist with the National Weather Service.