Kevin Myatt is The Roanoke Times' weather columnist.

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Many factors suggest this will be an abnormal winter.

Abnormally wet seems likely. An abnormally warm winter is possible, and the government forecasters are betting on this for most of the nation. But the last time El Nino was heating the waters abnormally in the central Pacific in 2003, we had an abnormally cold winter.

History suggests that, in Southwest Virginia, it will be either abnormally snowy or abnormally snowless. We've had 11 El Nino winters since 1948, and in 10 of those winters, we had snowfall either well above normal or well below normal.

But then, isn't every winter abnormal? What we call "normal" is the average of extremes over a 30-year period from 1971-2000. That includes some very cold and very warm winters, some years to shovel and some years we barely had to scrape. Very few individual winter seasons are anywhere close to what the statistics say is "normal."

Which makes what I'm about to do extremely abnormal in itself: I'm calling for pretty much a normal winter in terms of overall snowfall and average temperature, but a "normal" that will be an average of some wild extremes.

A normal winter here, based on statistics for Roanoke Regional Airport, means about 22 inches of snow for the season. I'm expecting 20 to 25 inches between Dec. 1 and March 30. I figure we'll be good for one 8- to 14-inch storm, another 4- to 8-inch storm, and a few little ones and sleet/ice mix events to make up the balance.

And with temperature fluctuations that lean to mild early, cold in the middle and warm late, I expect we'll end up within a few tenths of a degree of normal for temperature this winter.

Overall precipitation will probably be above normal by an inch or more by the end of March. That's the usual trend of El Nino winters here. We'll probably see lots of rain this winter. The question will be how often the cold air can get down to change rain into ice or snow.

I would be surprised if this is the kind of winter where the cold air sets in early and stays most of the winter, minus a few brief warmups.

Though it looks now like December will start with a sharp chill, after a few days of unseasonable warmth to end November, I'm not expecting the winter overall to get off to a very fast start. We've tended to do that lately, including last year, when December was 2 degrees below normal in an otherwise mild winter and featured ice or snow on Dec. 5, 9 and 15. We've had measurable snow during the first week of December in three of the last five winters, but only one of those turned into a winter that was colder and snowier than normal.

But the jet stream pattern over the North Atlantic doesn't seem to have the necessary roadblocks, yet, to crinkle the jet stream southward and lock it in place. So we may get some quick-hitting shots of cold air in December, but probably not extended, entrenched Arctic chill. Though it is always possible that a quick shot of cold air could time just right with a fast-moving storm system to trigger a winter storm, opportunities will be limited. (There may be at least some potential for this happening as early as next weekend ... stay tuned.)

A healthy snowpack has been building in much of Canada. This could be a big key in allowing Arctic air to build during the winter, and then hold it in as it moves south with more favorable jet stream patterns.

While El Nino looks healthy, it doesn't appear to be surging out of control as it has in some of our mild, wet winters. El Nino may be just strong enough to influence the southern branch of the jet stream, bringing wet storm systems in, but not strong enough to run off all of our cold-air masses.

If the same upper-air pattern that controlled our weather in May and again through most of September and October shows up about Jan. 1, with a deep southern dip in the jet stream over the eastern U.S., this could be a 1960 or 1996 kind of winter where snow is measured in feet. I'm betting on something less than that, but for cold air to arrive in two or three major shots between early January and early March lasting about one to two weeks each. It is during these times when we will have a shot at serious winter precipitation, provided the southern branch of the jet stream continues to deliver wet systems to our area.

I am concerned about the potential for a severe ice storm this winter, if we get in a cold-air damming situation with a shallow dome of cold air banked against the mountains at the surface while warm, moist air runs over it on the southern branch of the jet stream. I also think we're in for many, many borderline rain/snow and rain/ice/snow events.

Overall, I think this is going to be an interesting winter for weather geeks, with lots of ups and downs and some excruciatingly close calls between rain, ice and snow. It may be a troublesome winter at times, too, but probably not an extreme one -- some white, lots of wet, a little cold, and quite a bit of mild.

Ask me again in about three weeks and I may have a different set of answers.