The skyline is seen as the outerbands of Hurricane Irma start to reach Florida on Sept. 9, 2017 in Miami, Florida. Photo by Joe Raedle/Getty Images
LOS ANGELES—In California last month, two young children and their great-grandmother died in a wildfire that family members say they never saw coming.
In January, thousands of people were panic-stricken in Hawaii by a false alarm that a ballistic missile was about to strike the islands.
