12/23/2025
Here is a great CoCoRaHS volunteer story published recently by Village Media in Ontario. Enjoy and Happy Holidays from CoCoRaHS Canada!
AURORA - Every morning around 7 a.m., before most of Aurora has cleared the sleep from its eyes, John MacPhee is already outside in his backyard near Bathurst and McClellan, measuring snow.
Armed with a ruler, a gauge, and four decades of professional meteorology behind him, MacPhee records exactly how much snow has fallen overnight — sometimes down to the millimetre of water it contains.
He posts the results to local social media groups, but more importantly, he sends them to CoCoRaHS, the continent-wide volunteer precipitation network used by meteorologists, hydrologists, researchers, and emergency planners.
“After a 40-year career with MSC (ECCC), I’m still doing what I’ve always done,” MacPhee says. “The difference is that now I do it as a volunteer. The measurements you see are done on my own time, because they matter.”
Tracking every flake
On Dec. 10, he was up early measuring the season’s first heavy snowfall.
“As of 6:30 a.m. we had 4 cm in the last 12 hours, with a snow-water-equivalent of 4.4,” he reported. “By noon, we had an additional 7 cm. Moderately heavy. Dense snowpack.”
The numbers are precise because they have to be. Snowfall varies dramatically from one neighbourhood to the next, especially during snow-streamer events.
“Staffed weather observing stations are expensive,” MacPhee explains. “You find them at big airports or military bases. Automatic stations are also costly. That means gaps, big ones. Snow streamers and convective cells can pass right between them. Volunteers help fill those gaps.”
Pearson Airport might be the closest official station, but what happens in Aurora isn’t always reflected there, especially during lake-effect events.
“That’s why community data matters,” he says. “Precipitation is a discrete event. It can change sharply, even within a kilometre.”
A network where “every drop counts”
MacPhee submits his data to CoCoRaHS, the Community Collaborative Rain, Hail & Snow Network, which relies on thousands of volunteers across the U.S., Canada, and the Bahamas.
“CoCoRaHS is built on one idea: every drop counts,” the group says. “We use simple tools, proper training, and an interactive website. The data goes to forecast centres, then into archives for research or post-event analysis.”
MacPhee notes that Aurora has only two CoCoRaHS volunteers. He’s the only one who posts occasional public updates to Aurora community groups.
Once a week, more often in spring, he also measures snow-on-ground and its water equivalent.
“Hydrologists use that to gauge flooding risk,” he says. “It can influence real decisions.”
Hyper-local weather, one backyard at a time
MacPhee’s casual tone hides the precision of a lifelong scientist. In one recent post, he captured 8 cm of snow with a water equivalent of 6 mm — “not too heavy, good for a snowblower,” he added.
Later that day, when temperatures crossed 0°C, he updated the community again: settling had reduced the apparent depth.
He does it because he’s curious. Because he knows the data matters. And because it still feels good.
His measurements, he explains, are “valid over several square kilometres,” depending on the event.
“This morning’s reading is good for west Aurora near Bathurst and north of Bloomington,” he wrote Nov. 30. “Since this is a system, not a streamer, it probably gives a good estimate across town.”
MacPhee is modest, but his work is anything but small. It feeds forecasting centres, emergency assessments, and long-term climate research. It offers clarity during storms and nuance after them.
And in a growing town that increasingly faces unpredictable weather, his data, quietly gathered at dawn, is surprisingly essential.
“I just measure what falls in my backyard,” MacPhee says. “But you’d be amazed how useful that can be.”
