'Super rare' snow rollers form in Ottawa, watch here
Thursday, February 8, 2018, 6:25 PM - Sheila Nemcsok was treated to a rare winter phenomenon earlier this week.
While walking past the Supreme Court Thursday she spotted what appeared to be round bales of snow (watch video above).
The anomaly is what meteorologists refer to as "snow rollers."
"It's super rare for all the ingredients needed to produce snow rolls to come together. Of course strong enough winds are needed to physically roll the snow," says The Weather Network meteorologist Kevin MacKay. "The snow itself has to be dry enough to be pushed by the wind, but moist enough to stick together."
Temperatures also need to be slightly above the freezing mark.
Snow rollers have been known to occur in open fields and locations with sun and shade where snow density can vary.