Kevin Myatt is The Roanoke Times' weather columnist.

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As our world seemed to fly apart at the seams Monday, the wind kept roaring.

I wish April 16, 2007, were a date that we would have remembered only for an odd late-season nor'easter moving up the coast that caused the wind to blow down trees and knock out power as it spun a weird mix of snowflakes and blossom petals through the Southwest Virginia sky.

Focusing on weather for a few minutes in this difficult time, I have gotten quite a few e-mails lately asking about wind, specifically why it's been so windy lately and whether this is the windiest winter we've ever had.

I don't have the data at hand to answer whether the season as a whole was especially windy compared to others historically.

But I can tell you what drives big wind: Sharp contrasts.

Contrasts between hot and cold and between high atmospheric pressure and low atmospheric pressure force the wind to blow hard. Our region's mountainous geography assists in making Western Virginia an area especially susceptible to high winds during volatile winter and spring weather.

As I've detailed several times before, we have been on an unstoppable pendulum for nearly a year. Our temperatures have rocked between unusual warmth and abnormal cold.

The jet stream -- the river of air 4 to 7 miles up that moves storm systems across North America -- has made huge swings north and huge dips south for most of the past several months. The arcs northward are where warm air pokes unusually far to the north, while the southerly dips are where cold air sinks unusually far south.

When the temperature contrast between the cold air to the north of the jet stream and the warm air to the south of it is greater, the wind blowing through that jet stream is more intense. And in certain situations as storm systems move through, some of that strong wind can work its way to the surface.

Winds generally spiral out of high-pressure systems toward low-pressure systems. Think of a high-pressure system as a huge, stable mound of air pressing down and a low-pressure system as sort of a sinkhole in the atmosphere where there is a little less air to press down on the surface.

If you roll a ball off a hill toward a sinkhole, it will roll faster the steeper the hill is and the deeper the sinkhole is.

So it is with wind. The stronger the high-pressure system and the deeper the low-pressure system, the more wind blows out of one toward the other. Early this week, we were between a moderate high pressure system to the west and an extremely intense low-pressure system to the east.

Southwest Virginia's terrain plays a big role as well. The mountains poke up into fast winds aloft that would otherwise just zoom by overhead. The mountains catch the wind currents blowing from the west, and they tend to eddy toward the surface just to the east.

So those are a few answers about the wind. I wish I had better answers for the most difficult questions on all our minds right now.