A powerful extratropical cyclone developed c. November 18, 2024, in the Northeast Pacific and struck the Western United States and Western Canada.[9][10] The storm underwent bombogenesis, rapidly dropping its central pressure[11] to a record-tying level of 942 millibars (27.8 inHg).[9] This storm was the first of two storm systems to impact the U.S. West Coast during a 3 day period. The storm was associated with an atmospheric river that dropped large amounts of rain in Oregon and California. The Storm Prediction Center (SPC) issued a rare high risk of excessive rainfall in parts of Northern California, warning of "life-threatening flooding".[12]
Downed electrical power distribution line (left), garage and vehicles dented by falling trees in Cougar Hills, near Eastgate, BellevueTree at Green River College in Auburn uprooted by bomb cyclone winds.
The Eastside region of King County was the most heavily affected area of the Puget Sound region. The area's electricity provider, Puget Sound Energy (PSE), reported that more than 400 miles (640 km) of its transmission lines were impacted by high winds and it had contacted line crews from outside of the state to assist.[20] PSE repaired 47 of its 49 substations by November 23, but 66,000 customers still lacked service.[21] The Snohomish County Public Utility District had over 135,000 customers in Snohomish County and Camano Island without power; by November 25, it had restored service to 99 percent of customers.[22] Four northbound lanes of Interstate 405 were closed by a tree that fell into the highway near the Interstate 90 interchange in Bellevue.[23] The National Weather Service weather radio transmitter on Cougar Mountain near Issaquah went off the air during the storm.[24]
An Amtrak Cascades train struck a fallen tree in Silvana, between Stanwood and Marysville, at around 7:50 p.m. The tree pierced the locomotive's windshield but did not seriously injure the engineer or anyone onboard; service was temporarily disrupted while the damaged locomotive was towed away.[25][26] Amtrak cancelled several Empire Builder and Coast Starlight trips through the region in anticipation of the storm.[27]Link light rail service in the Seattle area was also disrupted by power outages; the northernmost section of the 1 Line was closed for several hours on November 19 and replaced by bus shuttles between Northgate and Lynnwood City Center stations.[28] The entire 2 Line between Bellevue and Redmond was suspended on November 20 and replaced by buses.[24]Washington State Ferries cancelled several sailings on its Port Townsend–Coupeville ferry route due to high winds across the Admiralty Inlet.[28]
The cyclone was associated with an atmospheric river reaching California from the tropics.[30]
Near the Oregon-California border, Interstate 5 was closed due to heavy snow.[31] In addition, the Avenue of the Giants was closed amid flooding. On Mattole Road in Humboldt County, a 98 mph gust was recorded, and at Crescent City Harbor in Del Norte County, an 80 mph gust was recorded.[32] Over 430 flights were delayed and 60 cancelled at San Francisco International Airport.[33] 23,000 power outages were reported in California.[8] Two people were reported dead in Sonoma County, with the first being found dead in a creek and the second in a flooded vehicle.[4]
Notes
^Observed offshore in Canadian waters. Maximum wind on land was 99 mph.
