Welcome to CoCoRaHS!   "Volunteers working together to measure precipitation across the nation."


7,044 daily precipitation reports received today as of 1/10/2012 9:43 PM EST

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The saying "Rain doesn’t fall the same on all" really proves to be true. How often have you seen it rain in your neighborhood and a few blocks away not a drop has fallen.

It is exciting to see that CoCoRaHS has expanded across the United States at a rapid pace over the past few years and is now the largest provider of daily precipitation observations in the country.   Even more exciting is the expansion of CoCoRaHS to our neighbors to the north.  In December 2011 CoCoRaHS Canada began with the province of Manitoba.  Other provinces will follow in the not too distant future. 

So when you have the chance please tell a friend or neighbor about this exciting grassroots effort to measure precipitation in the backyards of citizens from the Atlantic to the Pacific.  It's easy to join, takes only five minutes a day and is a fun way to learn about this wonderful natural resource that falls from the sky.  We are striving to have 30,000-40,000 active observers by the end of 2013 which will give us an ever clearer picture of the amount of precipitation that falls in our backyards.


CoCoRaHS is a grassroots volunteer network of backyard weather observers of all ages and backgrounds working together to measure and map precipitation (rain, hail and snow) in their local communities. By using low-cost measurement tools, stressing training and education, and utilizing an interactive Web-site, our aim is to provide the highest quality data for natural resource, education and research applications. The only requirements to join are an enthusiasm for watching and reporting weather conditions and a desire to learn more about how weather can effect and impact our lives.

Our Web page provides the ability for our observers to see their observations mapped out in "real time", as well as providing a wealth of information for our data users.

For more information, please click here: Information about CoCoRaHS

If you would like to sign-up as a volunteer observer and become part of our expanding network, please click here: "Join the CoCoRaHS Network".

Complimentary training is provided to help you become an effective weather observer.  Please check out your state page above (by clicking on your state) for a list of current training sessions in your local area.  If none are taking place at the current time, watch our "Training Slide Shows" and read our on-line training information.

The views and opinions expressed by CoCoRaHS's diverse group of volunteers may not necessarily reflect those held by the CoCoRaHS organization, its collaborators or its sponsors.

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Issue Tracking by Countersoft Gemini            Community Support by Countersoft Atlas               
Click here to sign-up to become a weather observer with the CoCoRaHS Network


Click here to view the article in Weatherwise magazine