Civic Science Precipitation Monitoring with CoCoRaHS, and a volunteer opportunity with LRWP!

The Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS), a national network of volunteer rain monitors, recently added some important new spatial and historical rainfall data mapping products by watershed at the HUC 10 level.

To access this data, go to

You can then click on the Watershed Maps, enter you address or zip code, and access the subwatersheds in the vicinity of your address. You can then click on your target watershed, and that watershed will come up with its area in acres and square miles, and a button for precipitation reports.

CoCoRaHs Watershed Map for Watershed Management Area 9

Click on the precipitation reports, and a “Configure Precipitation Report” box pops up. Click the drop down arrow, and you can choose between Daily Precipitation and Monthly Precipitation.

Daily Precipitation provides the Average Precipitation in inches for the pervious 24 hours for that subwatershed, along with the number of CoCoRaHS stations in the subwatershed. This data can be very useful for monitoring large rain events that can impact stream flows, flooding, and drought.

Choose Monthly Precipitation, and you can then choose monthly accumulated precipitation in inches for any month going back to 1998, and get the number of stations for that month.

Help track climate trends for the LRWP!

Can you help the Lower Raritan Watershed Partnership better understand climate trends? Let us know! We need a volunteer to extract historical rainfall data by month from CoCoRaHs data source and develop a monthly rainfall baseline so we can compare present and future monthly rainfall for climate trends analysis. We intend to eventually triangulate these data with our pathogens monitoring data.

Join CoCoRaHS!

The LRWP supports the CoCoRaHS ongoing campaign to recruit volunteers. Anyone can volunteer to report rainfall by signing up here and then purchasing and installing a $35 required rain gage.