California snow forecast: Atmospheric river poses flooding risks after 'bomb cyclone'
After a ferocious "bomb cyclone" battered the Pacific Northwest with dangerous winds on Wednesday, Northern California and southwest Oregon must now grapple with torrential downpours and high-elevation snow.
More than a foot of rain is forecast through Friday, causing potentially life-threatening flash flooding, rock slides and debris flow, according to the National Weather Service.
The pent-up moisture comes from an atmospheric river, known to cause extreme rain and snowfall in the West. Also sometimes called "rivers in the sky," these atmospheric regions function similar to rivers on the surface but can carry far more water than the Mississippi River.
Forecasters warn the heavy rain and high-elevation snow will come in two back-to-back systems, one peaking overnight Wednesday and the other peaking Thursday night. Rainfall of 12 to 16 inches is possible, according to the weather service.
The first wave will keep bringing heavy rain along the northern California coast and in southwestern Oregon through Thursday morning. The second one will peak along the northern California coast while posing a moderate risk along the northern Sierra ranges.
"The storm is just beginning," NWS Weather Prediction Center meteorologist Rich Otto told Paste BN. "The biggest surge is Thursday. We're looking at 10-15 inches of rain by Friday; some places, 20-inches."
Blizzard conditions forecast in Cascades, far northern California
Heavy wet snow will create whiteout and blizzard conditions in the Cascades in far northern California, and parts of Oregon and Washington, the weather service warned. Snowfall rates of 2-3 inches an hour and wind gusts up to 65 mph can make traveling nearly impossible.
Lower-elevation rain and high-elevation mountain snow are slated to spread inland toward the northern Great Basin and northern Rockies through Friday, the weather service forecasted.
Locally heavy snowfall will likely focus on the mountains across central Idaho and along the northern U.S. border.
California weather map
Oregon weather map
Bomb cyclone kills 2 women in Seattle suburbs
High winds brought by the "bomb cyclone" have proven to be deadly in the Pacific Northwest after falling trees killed two women in southeastern Seattle suburbs.
High winds also led to power outages for nearly half a million homes and businesses in Washington state, which also grappled with forecasted dangerous rain, flooding and snow in the region. Seattle saw its largest number of outages since 2006, the Seattle Times reported.
Akin to a winter hurricane, the "bomb cyclone" has brought wind gusts of up to 70 mph, downing trees, blocking roadways and smashing homes. When the storm passes, the region will still face days of rain, flooding and snow at higher elevations, according to the weather service.
National weather map
National weather radar
Contributing: N'dea Yancey-Bragg, Doyle Rice and Jorge L. Ortiz