Herewith - a twist on the old Twister parlor game - a weather quiz about tornadoes:

Question: Is it true tornadoes don't tend to hit cities?

Answer. Yes, in the same sense that if you throw darts at a board covered with a map of Tornado Alley, you're unlikely to hit a city. Because large cities make up a tiny part of the land surface in tornado territory, they are unlikely to be hit.

And while cities offer a little bit of discouraging "interference" to tornadoes, it's not enough to make much difference, according to Lynn Maximuk, meteorologist in charge at the National Weather Service in Pleasant Hill, Kan.

As proof, he points to Dallas, Detroit and Cleveland, all of which have been struck by tornadoes.

Question: Tornadoes have a reputation for rearranging the landscape. How far have they been known to fling objects in their paths?

Answer: Heavy items such as cars and appliances frequently are found hundreds of yards or even a of couple miles from where they started. Lightweight objects go much, much farther.

After a 1974 tornado dashed through Xenia, Ohio, checks were found in the southern suburbs of Cleveland, about 200 miles away, according to Maximuk.

Question: Is there a "calm before the storm" when a tornado is coming?

Answer: Yes - but only in a relative sense. Tornadoes generally occur in the late afternoon or early evening, after a predictable sequence of "noisy" events, punctuated by a couple of relatively quiet moments.

As tornadic conditions are developing several thousand feet overhead, the wind on the ground slows. That's because the tornado forming a few miles away is sucking in energy from all around, neutralizing the surface winds.

Then activity picks up again, with wind gusts followed by light rain, heavy rain, hail. Then the precipitation stops, giving a sense of unusual stillness, although Maximuk claims it's just "normal weather."

Then all heck breaks loose.

Question: What creates the dark, sometimes greenish, sky color when tornadoes are likely?

Answer: Large raindrops and suspended hail.

Question: Does opening the windows of a building reduce damage by equalizing air pressure? (Tornadoes are sinks of low pressure.)

Answer: No. Most property damage from tornadoes results from wind simply pushing structures over, as well as from flying debris - which can puncture people as well as objects.

In assessing damage from some of the nation's most virulent tornadoes, Maximuk said he's seen a playing card embedded in a 2-by-12-inch rafter, and a pencil that'd been driven into a round metal fence post.

"I've also been on disaster surveys where people had cigarette butts embedded in their skins," he said. "Anything moving at 250 miles per hour is a bullet."

Question: Which is more powerful, a hurricane or a tornado?

Answer: The Midwest easily whips the gulf coast for wind speeds. The highest wind velocity on record was the 315 mph tornado gust in 1990 that swept through Hesston, Kan.

Hurricanes, which essentially are ocean-going tornadoes, generally do not produce winds in excess of 150 mph.

Hurricanes cover a much broader area, however, often 200 miles or more across. Tornadoes are more typically a half-mile wide, or occasionally as much as one mile across.

Question: Mobile homes and their residents account for much of the death and destruction caused by tornadoes. What percentage of tornado deaths occur among people in mobile homes?

Answer: About 45 percent of people killed in tornadoes were in mobile homes when twisters struck. By contrast, only about 5 percent of Americans live in mobile homes.

Question: What states are within the area of most intense tornado activity?

Answer: "Tornado Alley" includes a wide band that runs through the middle of Kansas and Oklahoma, as well as the northwest corner of Missouri and a swath of the Texas panhandle.

A secondary band with fewer tornadoes encompasses much or all of Texas, Oklahoma, Kansas, Nebraska, Iowa, Missouri, Illinois and Indiana.

Question: How many tornadoes are reported in an average year in the United States?

Answer: It's somewhere around 1,000, with at least a couple hundred in "Tornado Alley," according to Fred Ostby of the Storm Prediction Center in Kansas City. Forty years ago, he estimates, the number reported was perhaps around 400. The higher number reflects not an increase in severe weather, but better technology, better communications and more chasers with camcorders.

Question: How many people typically die in tornadoes in a year in the United States?

Answer: It varies substantially, but the average death toll over the past 30 years is about 80 per year, according to Ostby.

Question: What is it about the Midwest that causes tornadoes?

Answer: The southern Great Plains is where air masses with different temperatures and humidity levels collide. Warm moist air from the Gulf of Mexico often meets here with cooler air from the north and sometimes with hot, dry air from the West or Southwest.

The differential in temperature and humidity provides the energy and the unstable setting that can generate a tornado.

Question: Where should one wait out a tornado?

Answer: You want to be as low as possible and as far from an outside wall as possible. Ideally that might mean the basement of a building, under a stairwell, inside a bathroom, or somewhere else with a maximum number of walls between you and the oncoming storm.

Severe storms forecasters no longer suggest seeking out the basement wall closest to the storm. In the middle of the basement is generally better.

Question: What's the best device for detecting a tornado?

Answer: The Doppler radar, which has been installed in the last few years, has been a boon to severe storms forecasters.

However, no technology yet has been able to take the place of human storm spotters who provide their services for free throughout the tornado region.

"We talk a lot about the technological advances that have been made," Ostby said. "But the old cliche holds true that the best tornado detection tool is the human eye."