Kevin Myatt is The Roanoke Times' weather columnist.

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Well, I told you last week that it was going to get cold soon. But honestly, I'm a little surprised it got this cold.

Going from a record high (77 on Dec. 1) to near-record lows in a week is a shock. Lynchburg and Bluefield, W.Va., set record lows of 12 and 9, respectively, on Friday morning, and Roanoke will do the same this morning if we drop below 15, the record for Dec. 9 set in 1992.

We did this same thing in reverse in early November, going from a record low of 24 on Nov. 4 to record highs of 78 and 79 on Nov. 10 and 11.

And we're about to have yet another shift, though it looks to be a gradual change this time.

This barrel of Arctic air has just about been emptied.

Through much of mid- to late November, when it was mild here, cold air was steadily building in western Canada and eastern Alaska.

It finally built up enough mass that it oozed southward with a shifting jet stream last weekend, propelled in part by the big low-pressure system that spun off the huge Midwest snow and ice storm.

But now, the cold-air mass has been almost entirely poured out into the continental U.S, and it's gradually warming.

There are no more reinforcements in the immediate future. Milder air from the Pacific will steadily take control next week, and we'll be back into the 50s for highs, maybe some 60s.

Somewhere in the northern latitudes, another pool of Arctic air will begin to build. In time, this air mass will begin buckling the jet stream and it will flood southward.

Where and when that happens will determine a lot about how the next phase of our winter goes. I'm guessing that happens right before Christmas. I like Dec. 22 as our first widespread snowfall date. But that's nothing more than a somewhat educated guess, following the rhythm of our up-and-down temperature cycle.

Next week, the moisture is likely to return too late for any wintry precipitation.

A low-pressure system is likely to develop somewhere in the south-central or southwest U.S. and track northeastward, far to our northwest.

It's probably a good thing the cold air is leaving, because next week's setup would favor an ice storm over snow if the cold air were hanging around.

With a low moving west of us, warm, moist air would be pulled over the colder air at the surface. That's a recipe for sleet and freezing rain rather than snow.

Few people like cold, dry weather, but even fewer like ice storms. A light glaze can be beautiful; anything more is a tree-breaking, power-killing mess. Go ask central Illinois about that right now. Some folks still don't have power after the Nov. 30-Dec. 1 storm.

So, once the dusting of snow melts away in the New River Valley and the temperatures warm enough to stay above freezing even at night, winter goes into waiting again.

Perhaps next week's low, once it passes, will help pull some Arctic air back to the south and winter will make a quick return.

Perhaps the El Nino pattern takes full grip and we get a series of mild, wet storm systems through the holidays, more like a chilly May than the Christmas season.

Or perhaps both of those happen together, mixing the cold with the wet.

That certainly didn't happen much during Round 1 of winter.

But the atmospheric boxing match that is our winter season has only just begun.