AP) A rare tornado touched down without warning Wednesday in the downtown area, killing at least one person and injuring more than 100. The black, swirling cloud struck about 1 p.m., uprooting trees and temporary buildings set up for a retailers convention. It also damaged the roofs of the 8-year-old, 20,000-seat Delta Center, home of the Utah Jazz, and the Salt Palace Convention Center. Windows were blown out at the nearby Wyndham Hotel.