A major storm continued to drop heavy snow and record rain Friday as it moved through Northern California, closing roads and prompting evacuations in some areas, after killing two people and knocking out power to hundreds of thousands in the Pacific Northwest.
Forecasters warned the risk of flash flooding and rockslides would continue, and scores of flights were canceled at San Francisco’s airport.
In Washington state, more than 185,000 people — mostly in the Seattle area — remained without power as crews worked to clear streets of electrical lines, fallen branches and debris. Utility officials said the outages, which began Tuesday, could last into Saturday.
Moderate rain was streaming across southern Oregon and Northern California on Friday morning, with showers over coastal Washington and heavier snow across eastern Washington, Oregon and Idaho, according to the National Weather Service’s Weather Prediction Center.
Gale warnings were issued off Washington, Oregon and California and high wind warnings were in effect across parts of Northern California and Oregon on Friday. Winter storm warnings were also in effect for parts of the California Cascades and Sierra Nevada.
Preliminary totals for the storm showed that 20 inches of snow had fallen in Soda Springs, California and Galane Blaine, Idaho, between Tuesday and Friday mornings, and 17.4 inches of rain had fallen in Venado, California, according to the center.
The National Weather Service extended a flood watch into Saturday for areas north of San Francisco as the region was inundated by this season’s strongest atmospheric river — a long plume of moisture that forms over an ocean and flows through the sky over land.
Flooding and road closures were reported in the North Bay, and the weather service warned residents throughout the area to expect disruptions during the morning and afternoon commutes on Friday. Rain rates have increased and shifted southward along the San Francisco Peninsula to the Santa Cruz Mountains with rain gauges reporting a few tenths to 1 to 2 inches so far, the weather service said early Friday.
In Humboldt County, the sheriff’s office issued evacuation orders and warnings for people living near the Eel River, which is forecast to break its banks, and urged residents to prepare for storm impacts throughout the week. Flooding closed Highway 1, also known as the Pacific Coast Highway, in Mendocino County north of Point Arena near the Garcia River and there was no estimate for when it would reopen, according to the California Department of Transportation.
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The system roared ashore Tuesday as a “ bomb cyclone,” which occurs when a cyclone intensifies rapidly. It unleashed fierce winds that toppled trees onto roads, vehicles and homes, killing at least two people in Washington.
Communities in Washington opened warming centers offering free internet and device charging. Some medical clinics closed because of power outages.
“I’ve been here since the mid-’80s. I haven’t seen anything like this,” Trish Bloor, a city of Issaquah official, said while surveying damaged homes.
Up to 16 inches of rain was forecast in southwestern Oregon and California’s northern counties through Friday.
Santa Rosa saw 6.5 inches of rain in the last 24 hours, marking the wettest day on record since 1998.
The Sonoma County Airport, in the wine country north of San Francisco, got more than 11 inches within the last 48 hours and the unincorporated town of Venado had about 12.7 inches in the same period.
Flash flooding, rockslides and debris flows were possible, especially where hillsides were loosened by recent wildfires, officials warned. Scott Rowe, a hydrologist with the weather service in Sacramento, said so far the ground has been able to absorb the rain in areas where the Park Fire burned this summer.
“It’s not necessarily how much rain falls; it’s how fast the rain falls,” Rowe said.
A winter storm watch was in place for the northern Sierra Nevada above 3,500 feet, with 15 inches of snow possible over two days. Wind gusts could top 75 mph in mountain areas, forecasters said.
In California, there were reports of more than 15,000 power outages on Friday morning.
Authorities limited vehicle traffic on part of northbound Interstate 5 between Redding and Yreka due to snow, according to California’s Department of Transportation. Officials also shut down a 2-mile stretch of the scenic Avenue of the Giants, named for its towering coast redwoods, due to flooding.
More than 200 flights were delayed and about 50 were canceled Friday morning at San Francisco International Airport, according to tracking service FlightAware.