January 28, 2014

Snow Rollers!

This fun phenomenon has been widely covered by local media and is the subject of many Facebook photos but I thought that out-of-towners might enjoy seeing what is entertaining us here in central Ohio as we deal with the polar vortex and the -11 degree temperature that we woke up to this morning!

Extreme cold temperatures, a couple of significant snowfalls, and strong winds have combined to make recent weather the major topic of conversation in central Ohio. Schools have closed, trash collection has been delayed, and many events have been rescheduled. It has, however, also brought delight: sunshine and some of the strangest and most surreal landscapes I've ever seen:



What are those weird clumps of snow that have appeared on local lawns and open spaces and look like bathroom tissue rolls that have arrived from outer space? Several people posted photos of them on Facebook and one friend identified them as "snow rollers". I had never heard of such a thing!

Venturing out, I saw lawns full of them and they were especially impressive on the nearby golf course and parks. Here is a close-up, with back-lighting to show the translucent center:



These rolls are not hollow--I split one open to see what it looked like:



You can see that the center is solid, since these rollers start out as small balls and pick up both thickness and length as they roll over the snow. (In some cases the centers are weak and blow out in the wind, leaving a hollow cylinder but all the ones I looked at still had a core) Think of snowmen you have made--you have to keep turning the ball in order to make the whole thing solid and round. Otherwise you would have a cylinder with a solid core and more hollow sides, just like in the snow rollers.

Wikipedia describes these rollers as a "rare meteorological phenomenon". I've seen references to them occurring this week in Illinois, Ohio and Pennsylvania, all areas that have shared some pretty unusual weather over the past several days.

In order for snow rollers to appear, a thin layer of ice has to form which is then covered by new snow that is around ice's melting point. Then if high winds blow over the landscape they can, so to speak, start the balls rolling and if the wind is strong enough but not too strong, snow rollers form. Here are a couple of photos showing the tracks of the rollers:




Here are some that didn't make it to cylinder size:



It looked like the tracks of most that I saw had been obliterated by the wind. In fact, the wind scoured the snow around many of them:



When you get to be my age you think you've heard of just about everything that weather can dish out, and then something like this comes along and you realize that maybe there will always be surprises in store, and some of them might even be fun. (Hmmm--I had similar thoughts about a rare meteorological phenomenon that I had never heard of a couple of years ago but it definitely wasn't fun--the derecho of 2012!)

Update 1/29/14:

We couldn't resist taking more pictures! 



Today we saw a few that were hollow, likely because the initial core was weak and blown out by the wind.

4 comments:

  1. Wonderful post, Deb. Thanks for sharing.
    Cheryl

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  2. Great article. We've got a few of these in the front and back yard. Hadn't noticed them in previous years.

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  3. Thanks for the pictures and explanation of snow rollers! I really enjoyed reading this.

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