"3:00 AM - And still coming down"
Raleigh, NC - January 2010 (Click to embiggen)
"3:00 PM - This shouldn't have happened until tomorrow!"
Raleigh, NC - January 2010 (Click to embiggen)
Snow is a rarity in my world. For the better part of this century (so far) we only saw snow once in every four years in Raleigh (though 25 miles west in Durham it was a different matter). So it looks like we got some, right? Yes and no. There is some snow in this mix, but I only know that because I saw it falling with my own two eyes. And it's neatly sandwiched between two layers of ice, which is they typical form frozen stuff takes when it falls from my sky. the difference between snow and sleet has something to do with the temperature at various places in the atmosphere and what freezes where and when. I'll let the alpha geeks explain that one. What I can explain is the reason for the ice cream sandwich effect. Simply put, the pavement was still above freezing when the snow started. It takes a long time for something as dense as concrete or asphalt to surrender its heat, so normally -- unless it's been below freezing for several days -- the first of the snow to fall will melt on contact, which bleeds more heat energy off from the pavement, and results -- ultimately -- in a thin layer of ice between the snow and the ground. The ice layer on top was simply sleet that fell on top of the snow. That's not nearly as bad as the light freezing rain that fell on top of it back in 1996. That turned things very nasty -- fast. And there's some talk that we'll have a encore performance of this phenomenon this week since daytime highs aren't expected to get terribly far above freezing, and rain/freezing rain is in the forecast for Tuesday and Wednesday. This could get ugly.Not that the weekend was any day at the beach. What you'd expect is for the day after the stuff came down -- when there'd been a cycle of thawing and freezing -- that the sandwich would become more dense and break off in slabs. In this case however, it was built in slabs. The photos in the second panel were taken just a few hours after the precipitation stopped. My brilliant idea was that if I shoveled the
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