Kevin Myatt is The Roanoke Times' weather columnist.

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• Coldest morning of winter so far likely across much of Southwest Virginia; Tuesday precipitation looking doubtful
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Old Man Winter's first round of punches will apparently pass without a widespread snowfall in our area.

With a storm that came together too late and too far east last weekend, a historic winter storm that passed too far west at midweek, and a potential Christmas weekend storm that will likely go too way too far south, we've been left holding a very cold bag full of bare trees and brown grass for the holiday weekend.

That's good news if you're traveling in any of the East Coast states, but bad news if you're traveling into the Ohio Valley or you're stuck here as a snow lover. I've heard from some snow fans this week. Take a deep breath -- winter has only just begun.

Winter's grip will relax next week, as we flex back to that familiar jet stream pattern that has been with us since October. The jet stream will dive southeast in the West and the rise more to the north over the East. That will return the cold, stormy weather to the west, bring milder weather to the east and keep the storms moving along the jet stream diagonally from the Southwest to the Great Lakes.

The issue then is how quickly will the pattern "reload" and bring another round of winter. Or, will the pattern become stuck with the cold air to the West? Or will it eventually re-align to bring more cold storminess to the East?

The reasons winter hasn't really set in, but has instead has jabbed us, have to do with the atmospheric pattern over the Atlantic Ocean.

I hope to get into this in more detail in the near future, but the North Atlantic Oscillation has remained in the positive phase rather than the negative phase. When the NAO is in the negative phase, a large high pressure system near Greenland acts as a block and the jet stream buckles southward over the U.S. in response, holding in place. Without this blocking high, the jet stream may buckle southward for a few days to bring cold or even frigid air, but there's nothing to hold it there and bounces back.

Translation: We can have shots of cold air, but they don't last. Any storm systems that would become winter storms have a very narrow window of time to develop or move through, or they'll miss the cold air and be rain storms instead. Or, as we just saw this week, the storm will move to our west and usher in mild air while other places get snow.

So a big part of forecasting this winter revolves around when, and if, the NAO flips to its negative phase. It almost always does flip, at least for a short while. When it does, our winter fortunes could change in a hurry.

Until then, Merry Christmas, even if it's cold and brown.