National Weather Service United States Department of Commerce

CoCoRaHS - The Rain Doesn't Fall the Same on All!

When you hear the rainfall amount from an official NWS gauge, have you ever said "That's not what I got!"?

 

CoCoRaHS LogoNWS Logo

 

CoCoRaHS - the Community Collaborative Rain, Hail, and Snow Network - is a Citizen Science program that lets anyone interested in taking precipitation observations make contributions. CoCoRaHS, which has its origins in Colorado in 1998, has spread across the nation and now covers all 50 states, Puerto Rico, the U.S. Virgin Islands, The Bahamas, and even into Canada! 

 

The data collected by our volunteers aids meteorologists, researchers, and the media to see and study precipitation patterns across the nation, within regions, as well as locally. The main duty of the observer is to collect and report daily precipitation measurements, typically between 7 and 9 am in the morning. Volunteers will be able to see their own "backyard" measurements in relation to other observers with . Furthermore, participants can map the daily collected observational data to their own computer.

 

The Florida Keys joined CoCoRaHS in October of 2007, with the first observer being an NWS employee on Big Coppitt Key. Since then we've expanded to almost 40 active observers! Local Volunteers (businesses welcome too!) continue to be needed to help grow this network across the Florida Keys. 

 

Visit the CoCoRaHS website at: https://www.cocorahs.org to learn more about the program and sign up to be a new observer. The CoCoRaHS website will guide you with getting set up and provides information on where you can order a rain gauge. 

 

One of the most common questions we hear is "I have a weather station (or specifically a rain gauge) already, can I just use that?" If you have a 4" manual rain gauge already it may be compatible, but more often than not a new one would be needed to ensure it is the same type used across the entire CoCoRaHS network. Automated weather observations (while these type of reports are certainly welcome here at the forecast office) are not permitted as part of the CoCoRaHS network. This is due to the higher accuracy of manual readings and also for the consistency of the network, making it apples-to-apples comparisons for the data (aside from possible gauge siting differences.)

 

Feel free to contact David Ross (CoCoRaHS Coordinator for Monroe County) at the National Weather Service Forecast Office in Key West if you have additional questions!