Interesting article from the Denver Post about snow science. But what I really liked about it was my misreading of one phrase:

“Once it gets packed down, it’s hard to peel it up with a plow blade,” he said. So in addition to plows Tuesday, Denver sent ninth graders and seven front-end loaders onto city streets to slowly scrape up packed ice, Kennedy said.

Actually, the article said nine graders. But high school kids would probably be cheaper.