This Thursday, Aug. 3, 2017 aerial image made from video provided by KABC-7 shows a motorist being airlifted from his truck after a flash flood hit in Acton, Calif. The Southern California desert community is cleaning up on Friday, Aug. 4, 2017 after thunderstorms unleashed muddy torrents through streets, threatened a commuter rail line and forced a rescue of the trapped motorist. The downpours struck Thursday afternoon north of Los Angeles in semi-rural Acton as monsoonal flow of extremely moist air streaming across the region boiled up into huge thunderheads. (KABC-7 via AP)