Life-threatening flooding will continue to wallop northern and central California into the middle of the week.
Several moisture-laden storms will crash onto the California coast, unleashing torrential rainfall and significant snow into Wednesday.
The storm train turned deadly on Saturday as a woman was killed on a golf course by a falling tree in San Roman, California.
Excessive rain to trigger flooding, mudslides
Rounds of heavy rain will unload over northern and central California for several days.
Cumulative rainfall from this weekend to midweek could surpass a foot across the northern California Coast Ranges and west-facing slopes of the Sierra Nevada. Two to 8 inches of rain are expected across the Sacramento and San Joaquin valleys.
“The siege of storms has the potential to wipe out or greatly erase the long-term drought conditions in the region,” AccuWeather Senior Meteorologist Alex Sosnowski said.
The rain will have a hard time absorbing into the soil with each passing storm. As a result, incidents of urban flooding, river flooding, mudslides and rock slides will only increase into midweek.
Flooding, mudslides and rock slides have already been reported in Santa Clara and Santa Cruz counties as well as the Bay Area early Sunday morning.
“Communities protected from levees around Sacramento and Fresno will want to keep a careful watch on the water levels,” AccuWeather Meteorologist Jordan Root said.
As snow levels remain high into Monday, heavy rain falling over snow-covered peaks in the Sierra could unload a torrent of water into the foothills.
“A tremendous amount of water will be released into area streams and rivers,” Sosnowski said.
Motorists will not only need to be aware of the threat for ponding of water on roadways, but also blocked roads due to flooding and debris flows.
Trees and power lines will be compromised due to the saturated soil. Gusty winds with each storm could easily knock down trees and cause power outages.
Some rain will reach Southern California, including Los Angeles and San Diego. These areas will experience more dry breaks in between rainy periods, which will lower the flash flood threat to a localized level.
Feet of snow to bury Sierra Nevada
Snow will remain confined to the highest peaks into Sunday night before the pattern takes a turn.
Snow levels will fall drastically from around 9,000 feet this weekend to around 5,000 to 6,000 feet Monday to Wednesday.
During the transition from rain to snow, travelers over the mountain passes, including Donner Pass, should use extreme caution. Wet roads could quickly turn snow covered and slick.
As the snow intensifies, travel will be extremely dangerous, if not impossible, over the mountain passes. Road closures are possible for a time.
By Wednesday, the northern California Coast Range and Sierra will be buried under several feet of snow.
“The extreme snow will be a boon for the ski industry and for the region's water reservoirs in the coming warm months," AccuWeather Senior Meteorologist Kristina Pydynowski said.
Outside of northern California, most of the state may experience a break from the storm onslaught late this week into next weekend.