A major winter storm hitting Northern California with rain and snow was expected to intensify Monday and bring travel headaches and the threat of localized flooding after an especially warm and dry fall in the U.S. West.

Light rain and snow that began falling on Sunday got heavier overnight. The multiday storm could dump more than 8 feet (2.4 meters) of snow on the highest peaks in California and Nevada and drench other parts of the states as it pushes south and east before moving out midweek.