CoCoRaHS

Click here for a power point presentation about CoCoRaHS

CoCoRaHS stands for Community Collaborative Rain, Hail and Snow Network. CoCoRaHS began with the Colorado Climate Center at Colorado State University in 1998 in response to the damaging Fort Collins flood in 1997.

The CoCoRaHS network is looking for enthusiastic volunteers to report rainfall, snowfall and hail information. Observers can be individuals, who take readings in their backyard, or school classes that take readings at their school. The measurements are made using high quality 4 inch rain gauges and hail pads. The information is used by a wide variety of organizations such as: The National Weather Service; television meteorologist; hydrologist; researchers; emergency managers and many others. Become a piece of the meteorological puzzle and join the other 8,000 volunteers from across the country and become a CoCoRaHS observer.

Please visit the CoCoRaHS website at www.cocorahs.org to learn more about the program. You can click on the "Join CoCoRaHS" link to become an observer. You can go through the on-line training or attend a training class to be on your way to become a part of the meteorological community.

The NWS Raleigh has been actively utilizing CoCoRaHS data for a variety of uses including real time precipitation and data analysis, severe weather operations, and post storm reviews. Some more specific examples are shown below:

CoCoRaHS daily precipitation reports are used extensively in the NWS Raleigh Daily 24 Hour Liquid Precipitation Maps
CoCoRaHS daily precipitation and snow reports are used heavily in the NWS Raleigh Daily Hydrologic Observations Summary

CoCoRaHS Intense Rain Reports have been used to allow forecasters to issue Flash Flood Warnings earlier and with greater confidence. A good example of this occurred on August 11, 2008. Forecasters were closely monitoring thunderstorms with very heavy rain and were concerned about the potential for 1 to 2 inches of rain during the next hour. A CoCoRaHS Intense Rain Report was received at 221 AM EDT reporting that 1.46 inches of rain had fallen in the past 20 minutes. While forecasters would have likely issued a Flash Flood Warning at a later point, the CoCoRaHS Intense Rain Report provided ground truth information and allowed forecasters to issue a Flash Flood Warning at 231 AM EDT. Subsequent Flash Flood Statements noted the heavy rain and flash flooding with a Local Storm Report providing details on flooding in Cumberland and Sampson Counties between 250 and 400 AM EDT.

CoCoRaHS Intense Rain Reports have been used for severe weather follow up statements. A good example of using a CoCoRaHS Intense Rain Report for an Urban and Small Stream Flood Advisory is from April 27, 2008.

CoCoRaHS Detailed Hail Reports have been used for severe weather verification. A good example of using a CoCoRaHS Detailed Hail Report for a Local Storm Report is from July 22, 2008.

CoCoRaHS Daily Comments have been used for Local Storm Reports and severe weather verification. An example of using a CoCoRaHS Daily Comment for severe weather verification is from July 6, 2008 when the comments from an observer near Asheboro provided details used in the verification of a Severe Thunderstorm Warning and a Flash Flood Warning.

CoCoRaHS Intense Rain Reports have been included in Area Forecast Discussions. A good example of using a CoCoRaHS Intense Rain Report for an Area Forecast Discussions is from July 5, 2008.

North Carolina, central North Carolina, and other local data plots
- North Carolina CoCoRaHS Stations
- North Carolina CoCoRaHS Data Plots (searchable by type, date, and location)
- North Carolina CoCoRaHS Precipitation Plot | Snow Plot
- Central NC CoCoRaHS Precipitation Plot | Snow Plot
- Triangle Metro Area CoCoRaHS Precipitation Plot | Snow Plot
- Triad Metro Area CoCoRaHS Precipitation Plot | Snow Plot
Event summaries, case studies and event maps