Kevin Myatt is The Roanoke Times' weather columnist.

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"Tornado Alley" became an expressway Wednesday.

Two years of relative quiet in the Great Plains' tornado belt ended with 70 reports of tornadoes Wednesday afternoon and evening from Texas to Nebraska. At least four people were killed.

There were a lot of deadly tornadoes in March and early April last year, but those primarily occurred farther east. Missouri, Illinois, Tennessee and Arkansas particularly suffered a year ago in three major outbreaks.

Tornadoes certainly are not rare in those states. It raises the question: Where is the real "Tornado Alley?"

Traditionally, the "Alley" has referred to the core states of the Plains: Texas, Oklahoma, Kansas and Nebraska. That area frequently experiences a long and active tornado season from March to June.

But many other central U.S. states also experience an abundance of tornadoes. Nowhere else on Earth is as geographically suited for clashes of dry air from high deserts and mountains, moist air from a warm ocean region (the Gulf of Mexico), cold air from a polar region and warm air from the tropics. Such intermingling in the right proportions spawns numerous tornadoes over a broad area.

A much wider definition of the Alley, therefore, could stretch from the Rockies to the Mississippi River, or even from the Rockies to the Appalachians.

When tornado researcher Thomas Grazulis put together his historic compilation of tornadoes ("Signficant Tornadoes: 1680-1991," known as the "big green book" to weather geeks) in the early 1990s, he pondered the question of which state could be crowned as the capital of tornadoes.

Depending on the criteria, the answer was different. Grazulis analyzed data from 1880-1991 to come to some surprising conclusions.

Some of the categories provided expected answers: Oklahoma and Kansas led in categories related to the number of violent tornadoes.

Certainly for number of tornadoes, nobody messes with Texas, because of its large area. But in terms of annual tornadoes per 10,000 square miles, Florida was the leader, probably owing to its year-round warmth.

In the number of tornadoes that had killed people per 10,000 square miles, Arkansas led; but in the number of deaths per 10,000 square miles, the surprise winner was Massachusetts, boosted heavily by 94 deaths in a 1953 tornado at Worcester. And Delaware led in the number of tornadoes that had caused injury per 10,000 square miles.

So while any overall look at tornado frequency favors the central states, these surprising numbers show that a major tornado is possible almost anywhere.

Virginia was not in the top 10 in any of the categories Grazulis considered. There are some advantages to not living in an alley.

A stormy week locally, too

There were no tornadoes, but many of you found yourselves in a hail alley Wednesday, especially from the New River south and east.

The local storms Wednesday were caused by a cold front slipping southward into the warm air many of you have enjoyed. That front is why you noticed a bit of a chill Friday morning.

With warmer temperatures building back, there could be more storms as new cold fronts enter the region Sunday and again toward the middle of next week.

That cooling trend I mentioned earlier this week is still on the way, but it will take a little longer to set in than earlier thought. It might not be as intense because the bulk of colder air will settle into the upper Midwest and New England. So we'll probably fit in a few more warm days early next week.