Yesterday many people awoke to find a rare phenomenon had taken place over night when they found these in theirs or a neighbor's yard. They are known as "Snow Rollers." Driving around today it was odd to find some yards or fields full of these making it look like a snowball fight had taken place there were so many of these to be seen. And yet other yards or fields had not even one, like my yard. According to Wikipedia here is what snow rollers are and how they are made:
A snow roller is a rare meteorological phenomenon in which large snowballs are formed naturally as chunks of snow are blown along the ground by wind, picking up material along the way, in much the same way that the large snowballs used in snowmen are made.
Unlike snowballs made by people, snow rollers are typically cylindrical in shape, and are often hollow since the inner layers, which are the first layers to form, are weak and thin compared to the outer layers and can easily be blown away, leaving what looks like a doughnut or Swiss roll.[1] Snow rollers have been seen to grow as large as two feet in diameter.
The following conditions are needed for snow rollers to form:
The ground must be covered by a layer of ice to which snow will not stick.
The layer of ice must be covered by wet, loose snow with a temperature near the melting point of ice.
The wind must be strong enough to move the snow rollers, but not strong enough to blow them apart.
Alternatively, gravity can move the snow rollers as when a snowball, such as those that will fall from a tree or cliff, lands on steep hill and begins to roll down the hill.
Because of this last condition, snow rollers are more common in hilly areas. However, the precise nature of the conditions required makes them a very rare phenomenon.
Interesting shot and thanks for the education. I've not seen any snow rollers here in my yard either but we have this year, for the first time I can remember, had frost quakes.
"As temperatures around Toronto and across Ontario drop to -20 Celsius (-4 Fahrenheit), residents are reporting frost quakes that are powerful enough to shake houses and rattle nerves.
Usually found in extreme polar regions, the recent outbreak of frost quakes, known to meteorologists as cryoseisms, are now affecting many residents of Toronto, Canada’s most populous city.
The weather-related phenomenon, which can feel like an earthquake, happens when water and moisture deep underground freeze as the temperature drops.
Frost quakes typically occur between midnight and dawn, the coldest part of the night, thus many residents are being jolted awake by the booming sounds. "
Wow--I've heard of this but didn't know much about these snow rollers. Such a freaky thing and I'm so glad you caught this wonderful image of one--count it as a FAV for me!
"As temperatures around Toronto and across Ontario drop to -20 Celsius (-4 Fahrenheit), residents are reporting frost quakes that are powerful enough to shake houses and rattle nerves.
Usually found in extreme polar regions, the recent outbreak of frost quakes, known to meteorologists as cryoseisms, are now affecting many residents of Toronto, Canada’s most populous city.
The weather-related phenomenon, which can feel like an earthquake, happens when water and moisture deep underground freeze as the temperature drops.
Frost quakes typically occur between midnight and dawn, the coldest part of the night, thus many residents are being jolted awake by the booming sounds. "