Sacramento, California – A powerful atmospheric river is setting up across California this week, bringing widespread heavy rain, mountain snow, and increasing flood concerns from Northern California into the south, with travel and infrastructure impacts expected to build quickly.
According to the National Weather Service and Weather Prediction Center, the moisture-rich system will meander across the state, producing periods of steady to heavy rain in lower elevations and prolonged snowfall in the Sierra Nevada. The most significant rainfall totals are expected along the westward slopes of the northern Sierra Nevada foothills through Tuesday, where flash flooding could become locally significant.
Runoff concerns are growing across urban areas, burn scars, and poor drainage locations, while landslides, mudslides, and rockfalls remain possible in mountainous terrain, especially in Southern California. Gusty winds may accompany the system, raising the risk for downed trees and scattered power outages, particularly in higher elevations.
In the Sierra Nevada, a prolonged heavy snow event is likely, with travel becoming difficult to impossible over mountain passes due to accumulating snow and strong winds. Snow-load impacts are also a concern as totals build through the week.
Residents are urged to avoid flooded roadways, secure outdoor items, and monitor local alerts. Additional watches and warnings are likely as the atmospheric river continues to affect California through the week.
