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Weather Observers of all ages are needed to study weather right in your backyard. 
Your observations will help meteorologists study local weather trends and could help save lives. 

If you have an interest in weather or weather data, we have an interest in you!


Upcoming CoCoRaHS Training Sessions:


Join us online for a virtual training session on Friday March 26, 2021 at 12:00 PM EDT.

Register by clicking here.


CoCoRaHS observers are needed in all areas. Contact us about becoming a volunteer observer or setting up a training session in your county. Just send an email to


It only takes a few minutes each morning to be a CoCoRaHS observer. 
If you can't make an in-person training session, you can still take training online and become an observer.


Sign up, learn more, or take online training at ...


Do you want to see what CoCoRaHS is all about? Watch these You Tube videos or read on!

Entertaining CoCoRaHS Information and Training Videos

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What is CoCoRaHS?

CoCoRaHS is an acronym for Community Collaborative Rain, Hail, and Snow Network. CoCoRaHS is a non-profit community based network of volunteers of all ages and backgrounds working together to measure precipitation. The network originated at Colorado State University in 1998 and has expanded to thousands of observers in over half of the United States. The NWS Northern Indiana office is helping to expand the CoCoRaHS network across Northern Indiana, Southern Lower Michigan and Northwest Ohio. 

Who can participate?

This is a community project. Everyone can help. The only requirements are an enthusiasm for watching and reporting weather conditions, a desire to learn more about how weather can affect our lives, a computer and internet connection to report your data, and an official 4 inch diameter rain gauge like the one pictured below. The ultimate goal of the program is to have one observer per square mile in urban areas and one observer every 36 square miles in rural areas. All observations from around the country can be viewed on the CoCoRaHS website and the data may be used by local media, engineers, insurance companies, emergency managers, and many others.

How does one join and become an observer?

Visit the CoCoRaHS home page and fill out an application. All new observers must complete brief training, either through a live session; a walk-in training session with a county coordinator; or complete the on-line training at Please see your local state's page on the CoCoRaHS site for more information.

CoCoRaHS in Indiana is made possible by: The Indiana State Climate Office at Purdue University and the National Weather Service. CoCoRaHS in Michigan is a joint effort by the Michigan State Climate Office and the National Weather Service. CoCoRaHS in Ohio is made possible by the Ohio State Climate Office, Ohio DNR, and the National Weather Service.

Where can I learn of new training dates in my area?

The NWS Northern Indiana will post CoCoRaHS training sessions for Northern Indiana, Southwest Lower Michigan, and Northwest Ohio on this page. For training outside of these areas, visit the CoCoRaHS page and click on your state. If you would like to schedule and host a training session for your area, or just want more information, please feel free to contact NWS Meteorologists Kyle Brown and Rachel Cobb at and