By Konstantine Fekos
A rare winter phenomenon startled countless Crawford County residents, most of which had never seen anything like it until they awoke to Monday’s frigid morning.
Snow rollers, large snowballs formed naturally by — you guessed it — rolling snow, dotted barnyards, roadsides and even school fields around the county, causing quite a stir in towns and rural areas alike.
“I noticed this phenomenon (Monday) morning looking out our kitchen window,” said Carolyn Coulter of Conneaut Lake. “The landscape was dotted with hundreds of hollow bales of snow made by high winds (Sunday) night.”
Coulter said her 87-year-old mother, a local resident all her life, was taken completely by surprise when she saw the unusual sight.
So was Judy Shumaker of Meadville, who said she’d never seen anything like it in at least 30 years.
“Woke up this morning to a yard full of snowballs a foot or more in diameter,” she said on Monday. “I counted 125 at least.”
What causes this rare occurrence exactly? A very specific combination of weather conditions, according to local and state meteorologists.
“You’ve got to have snow cover, obviously,” said Tom Kines, senior meteorologist for AccuWeather in State College. “That top layer has to be crusted over, thawed then frozen over again.”
A patch of fresh snow then needs to fall atop that thin icy layer, which occurs during temperatures close to the freezing mark, Kines added.
Then all it takes are some strong, but not overwhelming, wind gusts to get the ball rolling.
“Snow rollers are typically cylinders, almost like hay bales in how they form,” said Geoff Cornish, chief meteorologist for WICU-TV in Erie. “They’re typical in the Dakotas and Minnesota, windy climates.”
Meadville saw wind gusts of about 36 miles per hour early Monday morning, not enough to damage anything or break snow rollers apart, but potentially enough to push them along.
And during these perfect circumstances, snow rollers can sometimes be hollow inside and grow to a foot and a half or larger in size, according to Cornish.
“We’ve had so many little systems roll through in the past week so the snow didn’t stick to the soil and grass as much,” he said. “Loose snow doesn’t really adhere to the ice surface.”
“It’s like making a snowman,” Kines said. “You keep rolling that little ball of snow across the yard and it gets bigger and bigger, assuming it’s packing snow.”
And for all those conditions to come together at once is significantly uncommon, both meteorologists agreed.
“I haven’t been around them all that much,” Cornish said, “but this is the first time I’ve seen them in a local area. Some say they’re a little more common in hilly areas, but I don’t know if that’s entirely accurate.”