Whit Johnson reports on the FBI now saying the suspect acted alone and was inspired by ISIS and families of the victims share details about their loved ones; Pierre Thomas has the latest on the New Orleans attack investigation; Mola Lenghi reports as authorities say a highly decorated active-duty Green Beret is believed to be the driver in the fiery Cybertruck explosion outside the Trump hotel in Las Vegas; Jaclyn Lee has details after a small plane crashed through the roof of a building in Fullerton, California sparking a 4-alarm fire; and more on tonight's broadcast of World News Tonight.

Correspondent Victor Oquendo reports on the 60 million people across the country on alert for snow and ice; Reporter Alex Presha has the latest on the thousands of flights cancelled or delayed; Meteorologist Somara Theodore delivers the forecast as some states brace for their heaviest snowfall in a decade; Correspondent Trevor Ault has more details on the FBI investigation into the attack in New Orleans; and more on ABC World News Tonight.