California atmospheric river storm to bring flooding rain, debris flows, high winds, feet of snow

Posted at 2:48 PM, Jan 03, 2023
and last updated 2023-01-03 15:48:09-05

(THE WEATHER CHANNEL) — California is facing another threat of flooding rain, debris flows, high winds and feet of Sierra snow as a new, powerful storm tapping an atmospheric river approaches the state.

The storm is rapidly intensifying into what meteorologists call a bomb cyclone over the northern Pacific Ocean.

That low-pressure system will help drag a plume of moisture called an atmospheric river into California beginning Wednesday, and it will impact the state through Thursday.

This is the third such storm to strike California with an atmospheric river since late December, including a New Year's Eve system that caused serious flooding and debris flows.

Additional soaking storms are potentially in the pipeline for this weekend and next week, which could add to the flooding woes.

Flood watches have been issued by the National Weather Service for this storm in much of Northern and Central California, including for the San Francisco and Sacramento metros.

The peak of the heaviest rain in most of these areas will be from Wednesday morning into Thursday night or early Friday.

Flooding is likely in urban and poor-drainage areas, as well as on streams, creeks and rivers.

Debris flows are also expected, especially in areas of steep terrain.

The region is even more prone to flooding and debris flows right now because the ground has become saturated by the recent stormy pattern.

Don't attempt to drive through any flooded roadways and be sure to stay aware of the latest information if you are in a flood-prone area.

Rainfall totals from this storm in Northern California will be 3 to 8 inches in locations with hilly or mountainous terrain.

Lower elevations are likely to pick up 1 to 3 inches of rainfall, including as far south as Los Angeles.

Snowfall will be measured in multiple feet across the Sierra Nevada high country.

The storm will also blast Northern and Central California with strong winds.

Winds could gust up to 50 or 60 mph, potentially downing trees and knocking out power.

Trees are more prone to being downed because of wet soils.