Winter Storm Donald’s icy forecast not a typical scenario

Winter Storm Donald is expected to cause big problems when it comes to icy conditions.

But this storm isn’t presenting a typical scenario for freezing rain and ice concerns.

With a typical setup for freezing rain, you have cold air aloft where it’s snowing, a warmer above-freezing surge of air above the surface where that snow melts, and then a stubborn layer of colder, below-freezing air at the surface.

That layer at the surface is shallow enough that the rain doesn’t have time to re-freeze — when that happens, you get sleet– and instead it hits the sub-freezing surface and turns to ice on contact.

But this time it looks like our temperatures near the surface won’t be below freezing the entire time, and we’re still expecting icy conditions.

So what gives?

Because of how bitter cold this winter has been, the ground itself is still below freezing– way below freezing.

In fact, just two inches below ground in Green Bay, the soil temperature Wednesday afternoon was still 23 degrees.

That’s plenty cold enough to freeze any rain that falls on untreated surfaces.

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