NASHVILLE, Tenn. (AP) -- A volunteer effort that sprang from a devastating flood has grown into a nationwide network of weather observers whose data is used every day.

The Community Collaborative Rain, Hail & Snow network -- known simply as CoCoRaHS -- plays an important part in collecting precipitation data and in often alerting the National Weather Service to significant rainfall.

Ralph Troutman, a forecaster with the NWS in Nashville, is the Tennessee coordinator. He says the state has CoCoRaHS observers in all but three counties and is recruiting more.

The program is run out of the climate center at Colorado State University in Fort Collins, Colo. National coordinator Henry Reges says there are about 15,000 volunteers sending in daily information from all 50 states.

Information can be found online at http://www.cocorahs.org .