NEW : Bridge swept away by floodwaters in Giles County , Tennessee . Motorist in Tennessee drowns trying to cross a flooded road . Falling trees kill two people in Arkansas . Weather knocks out power to 42,000 customers in Kentucky .
NEW : Child swept away by floodwaters in Hickman County , Tennessee . Motorist in Tennessee drowns trying to cross a flooded road . Falling trees kill two people in Arkansas . Weather knocks out power to 42,000 customers in Memphis .