"A few minutes after 9 p.m. on Palm Sunday, April 5, 1936, a massive funnel cloud flashing a giant fireball and roaring like a runaway train careened into the thriving cotton-mill town of Tupelo, Mississippi, killing more than 200 people, not counting an unknown number of black citizens, one-third of Tupelo's population, who were not included in the official casualty figures. When the tornado hits, Dovey, a local laundress, is flung by the terrifying...