Kevin Myatt is The Roanoke Times' weather columnist.

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If there is a winter in which the "big one" could be a good thing for everyone, this is it.

Put aside your preconceived notions about snow -- passionate love or passionate hatred for most, it seems -- and consider the big picture.

We are in moderate drought, and very blessed not to be in severe or extreme drought like parts of Alabama and Georgia.

We've just finished Roanoke's driest November on record, and 2007 appears likely to be one of only four years in the past 60 not to see 30 inches of rainfall.

If we stack some dry winter and spring months on top of that, we could be in Atlanta's position of worrying about our water supplies come summer.

Ample snow is inarguably one of the best cures for drought. Melting snow moistens the ground more evenly than rain, which tends to run off rapidly. A big snow is like getting a slow rain over several days.

True, we could get our needed snow this winter in a series of small to medium events rather than one or two big storms. The problem is that there are many things arguing against a repeated pattern of smaller winter storms.

La Nina is occurring in the Pacific. The colder-than-normal waters in the central Pacific correlate strongly to mild and dry winter weather through much of the southern United States. We're on the north edge of the area where this correlation is the strongest.

During La Nina, we usually do not get a lot of those juicy storm systems that move out of the Pacific and cross the southern U.S.

Then there is that self-propagating nature of drought. It's much more pronounced in summer, when heat comes into play, but can be noticeable in winter, too.

Areas with dry ground have less surface evaporation, so the atmosphere tends to have less moisture. As a result, it's harder to get precipitation to occur over that dry ground. Some weaker systems that would cause substantial precipitation in wetter times might struggle to yield even a few droplets or snowflakes as the dry air sucks up what moisture is available.

The area of driest ground is to our south and southwest, between our region and our primary source of atmospheric moisture, the Gulf of Mexico. It's possible that has already had some impact in our last two potential rainmaking systems, producing scarcely anything.

So some of the weaker disturbances coming across the south that would typically give us our 2- to 4-inch snows may struggle as they come over the new "desert of the Southeast."

I think we'll have enough cold air, intermittently, for some winter storm threats, probably more cold days and less extremely warm ones than last winter.

The pattern over the northern Atlantic the next couple of weeks will be ideal to push Arctic air southward over us, beginning early next week. If that pattern becomes habitual, we could have a much colder winter than anyone is forecasting.

But the lack of moisture is a huge issue. So even if it's cold, we may be hard-pressed to get it to be white.

There's always a chance that one storm system can sweep into the Gulf of Mexico at just the right time, combine with Arctic air oozing south from Canada at just the right time and roar up the East Coast to spread a mighty wallop of white.

I could be wrong, and frequently have been in recent winter "guesscasts," but I think we're looking for that one home run if we want to see drought-easing snowfall. And the odds are against it.

If we can't get much snow this winter, we need the next best thing, which is a lot of rain during winter and spring. I think all of you snow lovers and snow haters despise cold rain.