Snow, Winds Combine For Rare Occurrence Of ‘Wind Snowballs’
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PITTSBURGH (KDKA) – People all around Western Pennsylvania woke up to some very unique looking shapes in their fields and yards.
Mother Nature had created thousands of sculptures called “snow rollers.” It’s a rare phenomenon
Meteorologist Dennis Bowman says two things contributed to helping form the wind snowballs, a wet snowfall that is good for packing, and winds strong enough to grab the snow and blow it continuously so it gathers more layers of snow.
“It’s just as you would do if you push a handful of snow along to start building a snowman,” Bowman said.
Bowman says it is somewhat of a rare occurrence for Western Pennsylvania because the wind isn’t often sustained to keep the snowballs going.
Winds were reportedly in the 30 to 40 mph over a period of a few hours.
“I just looked out and saw these big snowballs in the front,” says Rita Cunningham of Clarion.
But when she took a closer look, she says, “I thought I was on another planet. I had taken some letters to the mailbox and I saw that they had the hollowed out middle part there. Like little eyes looking at you.”
She’s never seen anything like it in her 79 years. The snow doughnuts, officially called snow rollers, also had Clarion University students scratching their heads.
“I was really confused,” says senior Shalynn Giovannitti. “I would actually go up lose and look at what they were, because I didn’t know if there was snow or something underneath the snow.”
Professor Tony Vega has taught earth science at Clarion for twenty years, but it’s the first time he’s ever seen snow rollers. He says conditions have to be just right for this phenomenon to appear.
“When the snow is perfectly wet, but not so wet to be heavy, the wind will pick it up and roll it,” he says. “And then it literally will snowball as it rolls across the surface.”
But if the wind blows too hard, you just blow apart. It also helps to have a sloping hill. But what about that doughnut hole?
“The first snow that’s picked up is the most fragile, and it will roll,” Professor Vega says. “And as it rolls around it picked up heavier snow, and it’s not bound very well. So what happens is it will roll, and as it rolls it picks up heavier snow around it. And then the wind will hollow it out. The loose snow in the middle will just blow right out of it.”
It won’t be long before the wind turns them into back into plain, ordinary snow. Sophomore Alecia Suto has the last word:
“It’s pretty interesting to see something like this because who knows when it will happen again.”
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