‘Bomb cyclone’ brings high winds and soaking rain to Northern California and Pacific Northwest
SEATTLE — What was expected to be one of the strongest storms in the northwest U.S. in decades arrived Tuesday evening, knocking out power and downing trees across the region. The Weather Prediction Center issued excessive rainfall risks beginning Tuesday and lasting through Friday as the strongest atmospheric river — a large plume of moisture — that California and the Pacific Northwest has seen this season bears down on the region. The storm system is considered a “bomb cyclone,” which occurs when a cyclone intensifies rapidly. The areas that could see particularly severe rainfall will likely reach from the south of Portland, Oregon, to the north of the San Francisco area, said Richard Bann, a meteorologist with the National Weather Service Weather Prediction Center. “Be aware of the risk of flash flooding at lower elevations and winter storms at higher elevations. This is going to be an impactful event,” he said. Hurricane-force winds, which are gusts above 121 kph, could be felt along the Oregon coast, according to the National Weather Service in Medford, Oregon. And near Seattle, conditions for a “mountain wave” were shaping up, bringing large, low elevation wind gusts that could cause widespread power outages and downed trees, said Larry O’Neill, director of the Oregon Climate Service and Oregon State University associate professor. “This will be pretty strong in terms of the last 10 or 20 years,” he said. “We’ve only seen a couple storms that have really been this strong.” About 94,000 customers were without power in western Washington as strong winds ramped up and snow fell in the Cascade Mountain passes Tuesday evening. More than 12,000 customers had lost power in Oregon, according to poweroutage.us. The National Weather Service in Seattle said a peak wind speed of 109 kph was recorded at Crystal Mountain near Mount Rainier. Winds were expected to increase in western Washington throughout the evening, the weather service said. In northern California, flood and high wind watches were in effect, and a winter storm watch was issued for the northern Sierra Nevada above 1,066 meters, where 28 centimeters of snow was possible over two days. “Numerous flash floods, hazardous travel, power outages and tree damage can be expected as the storm reaches max intensity” on Wednesday, the Weather Prediction Center warned. In Northern California’s Yolo County, crews spent Monday clearing culverts, sewers and drainage ditches to avoid clogs that could lead to street … “‘Bomb cyclone’ brings high winds and soaking rain to Northern California and Pacific Northwest” →