Some 84 people in Western New York belong to a network of weather spotters, and they let the National Weather Service know how much rain, hail or snow has fallen in their yards.
The national coordinator of the network, in a visit Monday to Buffalo, said at least 17 additional weather spotters are needed in the region.
Precipitation reports from a dense network of spotters provide the weather service "ground truth" to sometimes sketchy radar precipitation estimates, said Henry W. Reges of the Community Collaborative Rain, Hail and Snow network.
“It’s like increasing the number of pixels on your digital camera,” Reges said. “The more observers you have, the clearer the picture.”
The volunteer network can be more than just "backyard fun” for weather enthusiasts, Reges said during his visit to the National Weather Service’s local office.
During extreme weather, it can have real life-and-death implications.
“Precipitation is the most variable of all the elements,” said Reges, a Colorado State University meteorologist who coordinates the nationwide network of volunteers. “Precipitation can vary from block to block. Having more points out there helps us to find out what fell.”
The 19-year-old network was born out of extreme rain and flash flooding in Fort Collins, Colo., that killed five people on July 30, 1997. Only five miles separated places getting deluged with 14.5 inches of rain and spots with only 2 inches.
“No warnings went out from the weather service,” Reges said. “Had it been timely, we probably could have saved lives.”
Since its inception, the network grew from a few dozen volunteers in Colorado to a nationwide network of 20,000 that extends into Canada and the Bahamas.
National Weather Service meteorologist Jon Hitchcock is one of two active volunteers in Genesee County.
Hitchcock reported precipitation every day in 2016, one of only a half-dozen volunteers to do so in the region.
“The more volunteers we have out there measuring rain, the more likely we’re able to capture how much rain fell,” Hitchcock said.
Knowing where it fell and how quickly influences decisions in the forecast office.
“It helps us to put out more timely flash flood warnings,” Hitchcock said.
Warnings for rising waters in creeks and streams or for lake-effect snow can also be made using CoCoRaHS data.
The network requests volunteers to make precipitation observations at the same time every day. They can be reported online or by using an easy reporting CoCoRaHS app on a smartphone.