Kevin Myatt is The Roanoke Times' weather columnist.

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In what has been a warm autumn, it's going to take a hurricane to help bring in Arctic chill.

It seems a bit counterintuitive that a storm born in 80-degree waters can play a role in pulling Arctic air southward.

But that appears to be exactly what will happen over the weekend and into early next week.

Hurricane Noel killed more than 100 people in the Caribbean before it ever became a full-fledged hurricane, making it the deadliest Atlantic tropical system of the 2007 season. Through the weekend, it will be racing northward just east of the United States, possibly brushing Cape Cod or eastern Maine.

Weakening some and attaining characteristics of a nontropical low pressure system, it will spin across Newfoundland and toward Greenland. Its counterclockwise spin will then pull cold air southward from the Arctic Circle.

Hurricane Wilma performed a similar function for us in late October 2005, bringing some light accumulations of snow to eastern West Virginia.

But, really, Noel will only be the supporting actor.

The principal player in the weather pattern over the next couple of weeks will be a large dome of high pressure building over western North America. The high will bring extremely warm temperatures for this time of the season over most of the United States west of the Rockies northward into western Canada and much of Alaska.

Pay attention when it gets warm in the West during the late fall and winter, because that usually means it will get cold in the East.

The high pressure system pressing northward will buckle the jet stream southward, causing it to dip far to the south across the central and eastern United States. This will dislodge cold air in the Arctic region and force it south.

Pulled southward between the high pressure system's clockwise flow and the counterclockwise spin of the low over Greenland, the coldest air since the spring will move south across Canada into our part of the United States.

It will probably even be cold enough that, by Tuesday, northwest winds blowing over the mountains are likely to trigger the season's first snowflakes on the western slopes of the Appalachians, where snow typically falls when an upslope flow is present in winter. With lows dipping into the low 30s again, I cannot even rule out a few flakes drifting on the winds into the New River and Roanoke valleys.

We could use a large snowfall sometime in the next few months to help with the long-term precipitation deficit. But no rain or snow event that can make a real dent in the drought, similar to last week's soaking, appears to be on the horizon. Despite that rain, most of Southwest Virginia from Roanoke south is still rated in moderate drought, according to the National Drought Mitigation Center in Lincoln, Neb.

The northwest flow that will set up over the next couple of weeks will be mostly dry, as the Gulf of Mexico and Atlantic Ocean moisture sources are largely cut off.

So colder won't mean wetter. I know almost all of us like the sunny, dry days, but we could really use several days of dreariness before spring arrives.