The snow rollers seem to be pretty much all over western PA. Some large pasture fields I have seen have literally thousands of them. They range in size from a fist to a 5-gallon bucket. The bigger ones are usually hollow, but regardless of the diameter, they all seem to be about 12"-14" long. It is weird that the conditions were right for them over such a wide area. My nephew was loading a log truck at 0330 Tuesday AM and saw a field of them being made. He said they appeared in the space of 3 or 4 minutes, not over a long period. Maybe alien intervention, and I'm not talking Mexicans here.