Amateur Weather Observers Help Communities in Measurable Ways
DULUTH, Minn — In 1997, Fort Collins, Colorado saw 14.5 inches of rain in a span of 31 hours leading to flash flooding and several deaths. A year later, Colorado State University started the Community Collaborative Rain, Hail and Snow Network, or CoCoRaHS. It was created to hopefully prevent another similar tragedy. In the decades since, CoCoRaHS has grown into a network of thousands of volunteers across the country who measure and report the weather at their homes every day.
There are numerous organizations that rely on the rain, snow, and hail reports to better serve our communities. One of these is the National Weather Service which uses data collected after a storm to improve future forecasts.
“We use CoCoRaHS data every single day. And primarily the way that we use it is to understand what’s going on to verify our forecasts. If we don’t know, for example, how much snow fell, then we don’t actually know how our forecast did. But when we get that high density information, we can make better forecasts to better serve our community, and save lives and property in the meantime,” said Meteorologist Ketzel Levens with the National Weather Service.
The information gathered can be used to assess crop development and areas of potential drought. Snow cover and snow water content data can predict spring run-off. Rain measurements can help predict river levels and potential flooding like we saw at Rainy Lake last year.
CoCoRaHS is always looking for more volunteers to increase their coverage which will give us a better understanding of how local influences such as terrain and large bodies of water affect storms.
“There can be a ton of local influences. That can either be in the summer you get a thunderstorm that affects one neighborhood in Duluth, but not the other ones. In the winter it might be some lake effect snow band that drops 20 inches on somebody and somebody else only gets 2 inches. And so if you only have a couple observations in each place, you don’t understand what is happening locally, and that’s really important to understand the ramifications of that snow or rain that might fall,” said Levens.
There are some large gaps in the network in remote areas of Northeast Minnesota and Northwest Wisconsin. The National Weather Service and other organizations would like to see some of these filled to improve forecasts and outlooks.
Whether you are 8 years old or 80, measuring and reporting rain, snow, and hail can be fun and educational. All the training is free when you sign up, but there is a standardized rain gauge you will need to buy that runs about 35 dollars. After that, who knows, someday you might see your rain or snow report in my or Rusty’s forecast.