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Community Collaborative Rain, Hail and Snow Network


"Because every drop counts!"



The National Weather Service in Charleston, SC currently has nearly 250 active CoCoRaHS observers! As you can see from the map below, we are in need of observers in several counties, particularly across southeast Georgia. Sign up to become a volunteer weather observer here: Join CoCoRaHS! If you have any questions about the program, contact Emily McGraw or Julie Packett


What is CoCoRaHS?

CoCoRaHS (Community Collaborative Rain, Hail and Snow Network) is a non-profit, community-based network of volunteers of all ages and backgrounds working together to measure and map precipitation (rain, hail and snow). The network originated with the Colorado Climate Center at Colorado State University in 1998, thanks in part to the Fort Collins flood a year prior. CoCoRaHS has over 20,000 active volunteers across the United States, Canada, Puerto Rico, U.S. Virgin Islands and Bahamas. For a quick overview of the program, check out this short introduction video.

Volunteers take daily rainfall measurements in their backyard and then report the observation online. 

Who Can Participate?

This is a community project. Everyone can help - young, old, and in-between.  The only requirements are an enthusiasm for watching and reporting weather conditions and a desire to learn more about how weather can affect and impact our lives. 

Public, private and home schools are also joining! Learn about the "CoCoRaHS for Schools" program. 


How Do I Become an Observer?


Who Uses CoCoRaHS Data?

CoCoRaHS data 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.


Why Participate?

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. The more observations, the better as amounts can vary significantly over small distances. An added bonus - your observations get archived in the official climate record


Local Observer Highlight

Community Collaborative Rain, Hail and Snow Network - Wikipedia

"Weather observation has been my hobby for over 65 years and now I am so glad to be able to share my observations.  I have lived along the coast for all of my life both on Cape Cod in Massachusetts and here on Hilton Head for over 20 years.  I have observed many blizzards and hurricanes in my time.  Believe it or not the most damaging storms I have experienced were in New England.  The worst blizzard was the Blizzard of 78 where houses were washed into the sea.  I still remember the eye of the storm when we walked down to the beach and saw unbelievable destruction.  The worst hurricane was also on Cape Cod where the road was washed away and homes along the beach were lifted off their foundations and floated into the marsh.  Boats had to be removed by helicopter from the marsh. 

I will continue observing as long as I can.  Thank goodness for no snow here except for a rare occasion a few years ago.  Snow on palm trees is a sight that is not seen too often. "

-Diane, Station SC-BF-2: Hilton Head 4 N

Observer since February 2008



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