Kevin Myatt is The Roanoke Times' weather columnist.

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Europe is worried winter won't show up.

Unseasonably warm weather has settled in there, so much that many Alps resorts wonder if they're ever going to get a ski season going.

London even had a tornado last week that injured six people.

But the unseasonable warmth in Europe doesn't really seem that unusual to me. Extreme temperatures in one part of the world are usually balanced by opposite extreme temperatures in another part of the world.

We certainly saw this in much of last winter. While the continental United States was basking in unseasonable warmth for most of January and February, parts of Asia were experiencing record cold and snow. Last winter's first frost in 70 years in New Delhi was at least as bizarre as London's tornado.

You didn't have to go far to find the balance to Europe's warmth last week. Stepping outside your door would have sufficed.

While Roanoke and Blacksburg didn't set any record lows last week, it seemed that almost everybody around us did -- Lynchburg; Danville; Bluefield, W.Va.; and Bristol, Tenn., to name a few.

While measurable snow was spotty, it was certainly cold enough to make snow, so the Appalachian ski resorts may be outpacing the Alps this winter.

They'll need that extra snow to get through this week. Above normal temperatures returned Monday and are likely to hang on most of this week.

The up and down bounces in temperature, locally and globally, all relate to the position of the jet stream, that fast-moving current of air 5 to 8 miles above the ground.

As the seasons move from summer toward winter, the region around the North Pole gets colder as the sun hides below the horizon for increasingly longer periods of time.

The region of cold air expands, and the zone where warmer air and cold air meet moves southward. Generally speaking, the jet stream marks the boundary between the warmth of the subtropical regions and the cold of the Arctic regions.

Think of snapping a garden hose. The harder you snap it, the greater the rises and dips you will see along the length of the hose. That's what happens with the jet stream. It snaps north and south as atmospheric energy bends and buckles it. Where it snaps to the north, warm air fills the void. Where it pushes to the south, cold air fills in.

The northward arcs in the jet stream are called "ridges," while the southward dips are called "troughs." As you snap that hose, you will find out that every ridge is followed by a trough. So it only makes sense, that unseasonable warmth with a ridge in one region is accompanied by unseasonable cold with a trough in another.

Many forecasters swear on the study of "teleconnections" as an accurate means to predict weather trends. Teleconnections refer to the concept that a particular weather feature in one part of the world correlates directly to the development of a certain weather pattern in another part of the world.

This is an area of meteorology I haven't delved into in great detail yet, but the basis of teleconnections is what we've described above: Snapping the garden hose in one place has effects down the line.

Though undoubtedly there will be those who would point to Europe's current warm spell as Exhibit A for global warming, we should separate in our minds these short-term, regional up-and-down temperature anomalies from the global warming issue.

The patterns that cause broad regions of warmth and cold are fully natural and pre-existed any talk of man's effects on the atmosphere. The questions of global warming center on whether those warm spells are in small increments getting warmer, more frequent and longer, while the cold spells are getting a bit less extreme, less frequent and shorter. And you look at averages over several years, not a single season.

A little later this winter, we'll probably be reading news about massive snowstorms or cold waves in some of the same areas experiencing extreme warmth now. It seems that winter weather is like a dog always chasing its tail, never able to catch it and come to rest.