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Issues; by Staff Editor; 1 Page(s) The central part of the U.S.
gets many tornadoes, particularly strong and violent ones,
because of the unique geography of North America. The
combination of the Gulf of Mexico to the south and the Rocky
Mountains to the west provides ideal conditions for tornadoes to
develop more often than any other place on earth. The central
U.S. experienced a record-breaking week from May 4 through May
10 this year, when close to 300 tornadoes occurred in 19 states,
causing 42 deaths, according to NOAA's National Weather Service.
Storms that produce tornadoes start with warm, moist air near
the ground. Dry air is aloft (between altitudes of about three
to 10 kilometers). Some mechanism, such as a boundary between
the two air masses, acts to lift the warm, moist air upward. The
boundary can be a front, dryline or outflow from another storm-
essentially any kind of difference in the physical properties of
two air masses. "Kinks" in