Respond to prefers-color-scheme dark in app web views

Whether leaderboard ad sticky behavior is disabled

Follow section front redirects in Spectrum

Enable NLP source in PCS for load testing

Switch off the News Alerts Survey Widget when we have enough responses

Poll to determine if new LUF updates are available

Allows the winning A/B test variant to be turned on without Spectrum deployment

Show expanded byline information on articles

Show infinite scrolling sections in Assembler MultiView

Show option for NLP article summaries in Action Bar

Show NLP summaries collection recirc on article pages

A general feature flag for Recipe Features that aren't yet released

Show the Balance of Power component on the new Election subnav component

Feature flag for media team features that aren't yet released

Enable new Elections subnav on Site pages

Use new Orca video player for preroll plugin in Spectrum

If true, will use a spoofed user agent to scrape and summarize content from paywalled sources

flip back to old full page reload when new updates come in

Show the snow tracker (instead of the heat tracker) on Spectrum

Trump Campaign

Nick Wagner

A high-end atmospheric river is continuing to pummel Northern California on  Friday as it slowly meanders through the region on the tail end of a historic bomb cyclone that developed off the Pacific Northwest.

As soils fully saturate, water levels are rising, including on the Eel River south of Eureka where major flooding is forecast. At least moderate flooding is expected on additional tributaries, and more rain has yet to fall, further elevating the potential damage.

Alice Li

In a third-straight day of <a href="https://www.wpc.ncep.noaa.gov/qpf/excessive_rainfall_outlook_ero.php" target=_blank>major flood risk</a>, a Level 3 of 4 threat from the Weather Prediction Center covers parts of the coast north of San Francisco as well as portions of the northern Sierra Nevada and adjacent Central Valley. Santa Rosa, Sonoma, parts of Napa and Shasta are included in the Level 3 risk.

“Flooding impacts will again be rather widespread and locally significant,” the center wrote. It cited “additional concerns for debris flows, rock and landslide activity, and flash flooding involving burn scar locations.”

Flood watches run through late Friday or early Saturday from the northern San Francisco Bay Area to the state border. Some locations in southwestern Oregon and Northern California are also under flood warnings for similar periods due to ongoing river flooding and snowmelt.

As another low-pressure area swung by just offshore, it brought a new round of strong wind gusts to coastal and mountainous locations of Northern California into the Pacific Northwest, prompting high-wind warnings for gusts up to 60 or 70 mph. While an associated cold front dips southward, the atmospheric river will weaken and finally get on the move as snow levels come back down in chillier air behind it.

The Washington Post

Following the historic strengthening of a bomb cyclone,  around 200,000 people remained without power in Washington state early Friday, down from a peak about 700,000 Wednesday morning, <a href="https://poweroutage.us/">according to</a> <a href="http://poweroutage.us/">PowerOutage.us</a>. At least two people were killed in Washington as strong winds hit the region late Tuesday.

Attention turned toward the atmospheric river portion of the weather event Wednesday and Thursday. The storm’s target has mainly been Northern California and southern Oregon.

To the north of San Francisco, Santa Rosa <a href="https://bsky.app/profile/wxjerdman.bsky.social/post/3lbjxvzl72o2u" target="_blank">picked up 11.85 inches</a> Wednesday and Thursday. That beat its former two-day record high of 9.72 inches set in 1902. Parts of <a href="https://www.pressdemocrat.com/article/news/sutter-flooding-santa-rosa/" target="_blank">the city flooded Thursday</a>, including around the medical center where 150 people were temporarily stranded before being evacuated.

Rainfall totals of at least  5 to 10 inches have been common from southern Oregon to north of San Francisco. Several areas of totals past 10 inches have also popped up. Totals include the following in California as of early Friday:

13.84 inches at Clear Creek south of Mount Shasta

6.64 inches in Redding (up to 11 inches just west)

Locations in the north bay are up to 6-plus inches, while the city itself picked up 0.79 inches so far.

The Klamath Mountains in Northern California experienced an additional several feet of snow at elevations above about 3,000 feet into mid-Thursday before snow levels rose, limiting additional accumulation.

In and around Mount Shasta, an <a href="https://forecast.weather.gov/showsigwx.php?warnzone=CAZ082&warncounty=CAC093&firewxzone=CAZ282&local_place1=Mt%20Shasta%20CA&product1=Avalanche+Warning&lat=41.3225&lon=-122.3147">avalanche warning</a> was in effect due to the multiple feet of fresh snow mixing with or changing to snow in lower elevations. Periods of heavy snow also occurred in the Sierra Nevada around Lake Tahoe.

As another disturbance rides the jet stream, a second strong low-pressure system is skimming the Pacific Northwest coast. It won’t be as strong as the recent bomb cyclone, but it enhances rainfall and winds.

This second low-pressure area will help push the cold front and associated atmospheric river southward. It should deliver the heaviest rain so far to San Francisco on Friday. Snow potential in the Sierra Nevada is also ramping up — several feet will fall there through the weekend.

“Prolonged rainfall will result in an increased risk of flooding, an increased risk of landslides, and downed trees and powerlines across the North Bay,” the Weather Service office serving the San Francisco Bay Area warned.

About 1 inch to 3 inches should be relatively widespread in and around the city through Friday night. An additional 4 or 5 inches of rain could fall in heavily affected areas.

Very heavy snowfall is expected on Friday night into Saturday in the Sierra Nevada, where winter storm warnings are in effect. As much as 20 inches could fall in six hours at the height, with nearly 3 feet over 12 hours and storm totals past 4 feet.

As the heart of the atmospheric river shifts south, areas to the north will turn more showery rather than seeing persistent steady rainfall. Snow levels in the mountains will also fall again as cooler air moves in behind a front.

Although precipitation will linger into the weekend, it should be dissipating a good deal in intensity by Saturday. <a href="https://www.wpc.ncep.noaa.gov/qpf/ero.php?opt=curr&day=3">Much of the flood risk</a> by that point will be driven by fully saturated soil unable to hold any more rain.

Light rain might additionally march all the way to Southern California by later Saturday.

Perhaps followed by a short break, the next surge of the broken atmospheric river will probably move onshore by Sunday. For now, it appears to focus on Central and Northern California.

Ian Livingston is a forecaster/photographer and information lead for the Capital Weather Gang. By day, Ian is a defense and national security researcher at a D.C. think tank.

Ian Livingston

‘High risk’ for northern California flooding from Atmospheric River 

the-washington-post

APTOPIX Severe Weather Washington

Extreme Weather

Climate

Capital Weather Gang

Environment

Climate Lab

Weather

washpost

prism://prism.query/site,/weather?limit=20

Want to know how your actions can help make a difference for our planet? Sign up for the Climate Coach newsletter, in your inbox every Tuesday and Thursday.

Coverage of weather forecasts and weather event updates from across the nation and the world, including extreme weather and analysis of weather patterns.