Morgan Norwood reports on the intense turbulence that rocked a Houston-bound United Express flight, sending two passengers to the hospital; as internal changes at the CDC spark a leadership crisis, Selina Wang has details on the FDA’s new restrictions on COVID vaccines creating confusion over how and where Americans will get the vaccine; twenty years after Hurricane Katrina left a trail of pain and destruction along the Gulf Coast, Robin Roberts returns to the region to speak with the children impacted by the storm about the enduring emotional toll that's followed them into adulthood; and more on tonight’s broadcast of World News Tonight with David Muir. 00:00 Intro 02:27 Multiple passengers on Houston-bound flight injured after plane is rocked by turbulence 04:47 Cooler temperatures for millions across the U.S. over Labor Day weekend 05:41 Patient discharged as authorities reveal chilling new details in deadly Minneapolis shooting 08:12 New FDA restrictions on COVID vaccines cr...