Entire city of San Francisco under 'life-threatening' flash flood warning

Officials are warning San Francisco residents of dangerous flooding as a powerful atmospheric river, propelled by a churning bomb cyclone, moves through the region. An emergency phone alert went out to residents in San Francisco County, warning the public of “life-threatening” flash flooding. The warning was issued by the National Weather Service just before 1 p.m. Friday and is in effect until 3:45 p.m. The weather service said heavy rain is...