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Learn about the CoCoRaHS volunteer network of weather reporters

Posted at 7:31 AM, May 14, 2020
and last updated 2020-05-14 13:04:59-04

Are you a weather enthusiast? Do you enjoy talking about the weather? Tracking rain and snow that impacts your backyard? Running outside after a hail storm to measure the size of the stones? If so, CoCoRaHS might be of interest to you!

CoCoRaHS (pronounced KO-ko-rozz) stands for the Community Collaborative Rain, Hail and Snow Network. It's a network made up of volunteers from across the country that report rain and snow measurements.

These reports are very important because accurate precipitation measurement sites are few and far between in many areas, and precipitation can be highly varied from one location to the next.

The precipitation data helps a wide range of people, and organizations, better understand weather and climate. Look at the massive network of groups who use this data!


Across Wisconsin, we can get an idea of what the CoCoRaHS network looks like, and where there are current volunteers participating. This is the statewide reporting map from May 10, 2020.

There is a higher density of reports from SE Wisconsin compared to the rest of the state, which is great. But when we drill down and take a closer look, we can see reports from May 11th across Milwaukee County only show seven reports for the entire county. More reports would be a welcome site!

Participating is simple, all you need is a 4" diameter round plastic rain gauge and a computer with internet access (or you can use the app). Oh, and you need to be an early riser; CoCoRaHS asks that you input measurements between 6 am and 8 am each day. When it comes to reporting your data, the process should only take about 5 minutes a day!

Find the online application here.

Training is required before you are able to participate. You can find the training here.

CoCoRaHS FAQ's can be found here.

While many of us are spending extra time around the house, and maybe looking for new activities or groups to get involved with, CoCoRaHS is a great opportunity!

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