Citizen scientists use rain gauges to assuage information drought

Have you ever seen the edge of a rainstorm, where the curtain of falling water abruptly ends?

The hyper-local nature of weather patterns means that a few weather stations spread across an area aren't enough to accurately represent the amount of precipitation that's fallen in a region. This has major impacts for meteorologists trying to predict flood, fire or snow emergencies.

This is where the Community Collaborative Rain, Hail and Snow Network, or CoCoRaHS steps in. With volunteer contributors throughout the state and nation, CoCoRaHS compiles a fine-scale map of precipitation, which is used by a broad scope of experts (including meteorologists, hydrologists, emergency coordinators and farmers).

Ketzel Levens, a CoCoRaHS regional coordinator for the Minnesota Northland/Arrowhead Region, joined the KAXE Morning Show to talk about the program.

"This is a volunteer citizen science network of folks who measure and map precipitation in their own backyards, essentially using standard equipment," Levens said.

Volunteers trained by CoCoRaHS use a standard 4-inch rain gauge, hail pads and a ruler to measuring rain, snow and hail, then enter their data through the CoCoRaHS website or phone app.

This network of volunteers are particularly vital in "areas where precipitation can vary greatly over short distances — places like around Lake Superior, for example, where you have a huge lake influence, things like that," Levens said.

She continued, "As we know, thunderstorms in the summer classically can hit somebody really hard and person a couple blocks away gets almost nothing. But the kind of standard networks that exist to measure that precipitation don't exist on the scale of ... neighborhood blocks. They exist on the scale of 10, 20, 50 miles apart in between observing stations."

CoCoRaHS is currently recruiting volunteers through the Rain Gauge Rally 2026, and observers are particularly needed in rural areas.

Levens noted they're working with the Koochiching County Soil and Water Conservation District to offer free rain gauges in the Rainy River Watershed.

"Just to really try and up the amount of observations we have there because it's so rural," she explained.

The conversation with Levens covered a lot of ground, ranging from the surprisingly specific ways rain falls in Duluth to how KAXE listener Susan from Cotton used CoCoRaHS data to make decisions about wildfire evacuation in spring wildfires of 2025.

"Believe me, reporting all the zeroes matters!" Susan said, in response to Levens' explanation of how zero precipitation reporting is crucial.

Listen to the full conversation above, including our very own John Latimer's experience as a volunteer with CoCoRaHS.

Funding for this project was provided by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR).