Kevin Myatt is The Roanoke Times' weather columnist.

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Round and round she goes, where she stops, nobody knows.

It's a Thanksgiving week mess along the East Coast, because of a rogue, whirligig low-pressure system that has nowhere in particular to go and no reason to hurry.

If this were a month later, we'd probably be talking about some heavy Christmas week snowfall for some areas. There were some reports of snow in the Carolinas on the western edge of the precipitation shield Tuesday, but the cold air isn't thick enough right now to support a large winter storm. So they're left with chilly, windy rain by the buckets in places such as the Outer Banks of North Carolina and the Tidewater of Virginia.

Here in Western Virginia, we're a bit far to the west to experience primary effects from this storm system. It might fling a few showers around the next couple of days, and the winds will pick up from the north, but it will probably not be especially soaking or gusty. Don't entirely rule out a few pellets of sleet or a few flakes of snow, but the bulk of the moisture appears to be too far east and the cold air not thick enough for more than that.

Generally expect partly to mostly cloudy skies with the kind of chill that matches Thanksgiving -- cool enough for a fireplace at night, but not cold enough to keep from going outside to throw the football around in the afternoon.

The storm system off the East Coast is the surface reflection of a "cutoff low" aloft. A cutoff low is one that has become separated, or cut off, from the jet stream.

Think about a swing set for a moment. If it you built up enough momentum on a swing, it would be possible to flip over the swing set in a circular motion. It wouldn't be very comfortable, but it would be possible.

A cutoff low forms in a similar manner. As a pocket of strong winds approaches a deep trough, or southward dip, in the jet stream, that energy swings through the trough. But sometimes, the winds have enough momentum to swing all the way around the trough and back over it, forming a circle of strong winds aloft. What was the trough then breaks free of the jet stream itself, and a circular cutoff low whirls counterclockwise apart from the jet stream.

Without the jet stream to guide it, this isolated swirl of wind high in the atmosphere doesn't have anything to push it anywhere with any authority. So it drifts, whirling in place and slowly moving. This one will probably find enough of a push to glide slowly north, swirling persistent rain along the Eastern Seaboard along the way.

In time, a cutoff low either gradually spins down and diminishes, or eventually gets picked up and pushed away by a new jet stream trough dipping down.

Cutoff lows can become very important players in our winter weather. Cutoff lows near Hudson Bay can continually swirl frigid Arctic air over the United States, while one near Newfoundland can help redirect the jet stream far enough to the south to increase the winter storm threat in our region.

Conversely, a cutoff low in the northern Pacific can continually steer milder Pacific winds far to the north, bringing mild weather to much of the U.S.

This one will be a nuisance, with the potential for flooding rains along the Atlantic coast from North Carolina northward, and also beach erosion as strong east and northeast winds continually beat the waves.

For many, even without the snow, this will become the memorable "Thanksgiving Nor'easter of 2006."

Winter forecast coming

In Saturday's column, I plan to continue my annual exercise in futility by expounding on the dubious speculations known as my winter forecast.

Two years ago, I nailed it. Last year I bombed big-time.

But it's a brand new season -- and a thoroughly confusing one. I'll do my best to make some sense out of it.