Some Californians brace for 'atmospheric river,' expect worst floods in a decade

Posted at 2:24 PM, Jan 06, 2017
and last updated 2017-01-06 18:15:46-05

Californians in the central and northern areas of the state are preparing for the worst flooding in more than a decade, as a storm system is on track to make its way California this weekend.

The event, fueled by an "atmospheric river," is expected to drop feet of snow in the mountains, primarily in the Sierra Nevada. Several inches of rain are also expected throughout the central and northern half of the state, according to the National Weather Service (NWS).

An "atmospheric river" is known as thin system of moisture that originated in the tropics or subtropics. 

While the promise of rain and snow is welcomed news as the state's long-term drought continues, what may be left behind isn't as welcomed. 

Flash floods and mudslides in areas throughout the San Joaquin Valley, Sacramento Valley and along the San Francisco shoreline may occur, as water levels increase from rain and snow melt in the Sierra Nevada and other high mountain tops. The NWS has issued flash flood watches for several mountain ranges and valleys extending from Bakersfield to Redding through the weekend.

Just this week, Mammoth Mountain was hit by at least seven feet of snow in 48 hours and expects about 20 feet of snow to accumulate in the area through Jan. 13.

Small rivers and streams are also particularly susceptible to flooding. Rising water levels in the Carson, Cosumnes, Merced, Susan and Truckee Rivers may cause flooding to low-lying areas, roads and urban centers, according to

Southern California is likely to see some light rain throughout the weekend, but not up to the levels expected to hit central and northern portions of the state, which could hit up to a foot of rainfall.