MOBILE, Ala.— Mobile Infirmary Medical Center quickly resumed normal operations following a Christmas Day tornado that caused external damage and temporarily knocked out power. The 493-bed facility, the largest in the southern part of the state, relied on its backup generator in the aftermath of the storm, but its power had been restored as of Dec. 26, said Mark Nix, president and chief operating officer of Infirmary Health System, the system that operates the medical center. No patients needed to be evacuated but some were moved to another wing, he said in an e-mailed statement. “The tornado caused several ceilings to partially collapse, and there was exterior damage to the back of the hospital,” Nix said. “However, no patients were injured and patient care was not impacted.” He added that the hospital is operating as normal “with the exception of cleanup and stabilization.” The Christmas Day storm delivered a wallop to much of the middle of the country, bringing snow up north and several tornadoes to the Gulf Coast before charging up toward the mid-Atlantic region the day after.