• Basic Information
• Additional Info

Basic Information

• Project No. and Title: WCC1012 : Managing and Utilizing Precipitation Observations from Volunteer Networks
• Period Covered: 10/01/2024 to 05/20/2025
• Date of Report: 07/21/2025
• Annual Meeting Dates: 05/20/2025 to 05/22/2025

Participants

*Note* Many of our participants were not able to attend the meeting this year due to constraints and uncertainty and therefore CoCoRaHS held an internal meeting that was still relevant to the coordinating committee's objectives. Therefore, some of this report may be limited to what could be accomplished with the attendees listed below: Nolan Doesken (virtual) - Colorado State University (retired) Russ Schumacher - Colorado State University Henry Reges - Colorado State University Steve Hilberg - Colorado State University Julian Turner - Colorado State University Noah Newman - Colorado State University Carol Stolz - Colorado State University Dani Talmadge - Colorado State University Tony Bergentino (virtual) - Wyoming State Climate Office Matt Spies - Connecticut CoCoRaHS State Coordinator

Accomplishments

Impacts

1. CoCoRaHS data are used in grids by PRISM, which in turn are used by the crop insurance industry. CoCoRaHS data save tax payers millions and millions of dollars per year, with $100 billion of crop value insured every year.
2. In addition to Condition Monitoring Reports, CoCoRaHS rainfall and evapotranspiration measurements are incorporated into drought monitoring tools at the Midwest Regional Climate Center: https://mrcc.purdue.edu/cliwatch/drought/drought.jsp
3. CoCoRaHS is a source of new U.S. Coop observers
4. CoCoRaHS data are used by Natural Resource Conservation Service range condition recommendations, which in turn feeds decision by producers (stocking).
5. CoCoRaHS Condition Monitoring Reports have had a significant positive impact on the assessment of drought. For example, The North Carolina Drought Management Advisory Council incorporates report information into the weekly state drought map. NWS Forecast Offices in the Carolinas reported using the reports to recommend the drought status in their county warning areas and for other products and forecasts (e.g., fire weather warnings). US Drought Monitor map authors download the reports each week as a GIS layer, as part of their “convergence of evidence” in designating drought.
6. CoCoRaHS precipitation data and Significant Weather Reports are used to verify radar, and are part of NWS Local Storm Reports (LSR) during severe weather and snowstorms. They are used in “event maps” for significant storms by NWS offices.
7. CoCoRaHS Snowfall data are used to secure federal snow removal aid (FEMA). Snowfall used to determine resolution of snow plowing contracts.
8. The National Hurricane Center uses CoCoRaHS for post‐storm analysis.
9. CoCoRaHS data provides the observational density to ensure the quality of both networks (CoCoRaHS and COOP).
10. CoCoRaHS data used to quality control U.S. Cooperative data, and vice versa.
11. CoCoRaHS data are used to help verify State Records from the COOP network, and high quality CoCoRaHS observations can also set records for precipitation.

Grants, Contracts & Other Resources Obtained

Publications