Trevor Ault reports on the massive, blinding dust storm – also known as a haboob – that swallowed Phoenix, knocking out power to thousands and even grounding flights, as monsoon rains swept in; Matt Gutman has details on pop star Taylor Swift and NFL star Travis Kelce announcing their engagement after dating for two years; Diane Sawyer sits down with Bruce Willis' wife, Emma Heming Willis, who opens up about her husband's deeply personal battle faced by so many families across the country, when a loved one faces down dementia – and the challenges they are overcoming together in the ABC special "Emma & Bruce Willis: The Unexpected Journey"; and more on tonight's broadcast of World News Tonight with David Muir.

While a motive in the Annunciation School mass shooting remains under investigation, Alex Perez has the new video showing the chaos inside the church as gunfire erupted during Mass and the father of the 8-year-old killed in the attack speaks out; Mary Bruce has the latest on the dozens of workers who walked out and the four top officials that resigned in protest at the Centers for Disease Control and Prevention following the ousting of the agency's director; Victor Oquendo has details on the horrific alligator attack in New Orleans that police say has left a missing 12-year-old boy dead; and more on tonight's broadcast of World News Tonight.