Kevin Myatt is The Roanoke Times' weather columnist.

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• Sprinkles or flurries possible Tuesday, but maybe something bigger for the weekend?
• For now, it looks like a quiet, mostly mild week ahead for SW Virginia
• Coldest morning of winter so far likely across much of Southwest Virginia; Tuesday precipitation looking doubtful
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We're riding the wave between mild and cold. And riding on a wave means we'll get wet.

Fronts and low pressure systems are whizzing by at a dizzying rate on what has become a more or less "zonal flow" for the jet stream. A zonal flow simply means it's blowing generally west to east, with less northerly or southerly dipping than we would expect in more prolonged warm or cold periods.

As a result, it has rained at least a little bit in Southwest Virginia every day this week, and it will likely rain at least some each day through the weekend.

The jet stream is generally the dividing line between cold air to the north and warmer air to the south. Mostly, it has stayed north of us, keeping things fairly mild for this time of year -- cool, but not cold. But undulations in the jet stream with each passing storm system are causing temperatures to fluctuate, ranging from Tuesday's cold rain in the 30s and Thursday's dank fog in the 40s to what could be a windy push into the 60s today.

Cold air presses south again on Saturday just in time for the next storm system in the chain to spread moisture over it. It is possible that the next shield of precipitation will begin with some freezing rain or sleet here and there.

But then milder air moves in Sunday as the storm passes well to our north, bringing another round of rain. By Sunday night, the low will drag a cold front through, and a breezy round of mountain snow showers will likely follow Sunday night into Monday.

We may do something like this all over again in the Tuesday to Christmas period.

For anybody wanting a white Christmas, a more southerly track of cold air could yield something a little wintry. Likely, though, it will be another cold rain, possibly beginning as spotty ice and ending with snow showers -- just like this weekend.

Today, a copious snow exceeding 1 foot in places will be passing hundreds of miles to the north across southern New England as we get a few showers and spurt of warmth. Saturday night and Sunday, we may get another soaking rain, with 1 to 2 inches across much of Southwest Virginia.

This pattern is at least good for drought relief, even if it's dreary for sun lovers and snow fans. But what weather pattern will follow this one?

Atmospheric signals and computer models are yielding mixed signals as we peer toward 2009.

But I don't believe we're going to get through the next couple of months without experiencing at least one two-week period of bona fide winter, which would be more real winter than we've had in at least four years.