Atmospheric river, ‘bomb cyclone’ combine to batter N. Cali
Matt Simons
OAKLAND, Calif. (CN) — What happens when a bomb cyclone meets an atmospheric river? A whole lot of rain, as it turns out.
Northern California is bracing for high winds, heavy rainfall and possible flooding across the region after the National Weather Service announced an atmospheric river taking aim at the region. The storm will combine with an existing bomb cyclone currently tearing through the Pacific Northwest to bring about extreme weather patterns.
“It's got all the headlines,” said Brian Hurley, a senior meteorologist with the Weather Prediction Center. He noted the storm has been compared with some of the larger storms that usually batter the East Coast.
“In that way it is comparable. It's got the wind, it's got the rain and the heavy snow,” he explained.
Far north counties like Humboldt and Siskiyou will likely see the worst of the storm, with up to 16 inches of rain expected in some regions, as well as flash flood warnings and massive power outages.
Wind speeds are expected to reach between 45 to 55 mph throughout the region.
Although no deaths have been reported in California at this time, the storm has already shown deadly effects in the Pacific Northwest, causing widespread power outages and leaving at least two dead in Washington state.
Utility companies in Northern California have positioned their workers to respond to potential power outages caused by falling trees and other weather effects.
“PG&E has been pulling resources from unaffected areas of our service territory and bringing crews up north to assist local crews,” said Paul Moreno, a spokesperson for Pacific Gas & Electric, which provides power to most of Northern California. “This will allow us to get the power back on more quickly.”
Moreno said power outages have most heavily affected the North Coast region from the Golden Gate Bridge northward, particularly Humboldt County. He added that although the utility company was making good progress on restoring power, some areas proved harder than others.
“We do have some pockets where there are more customers without power than others, like in the Eureka and McKinleyville area,” he stated.
Although the worst of the storm will be relegated to more northern counties, areas like the Central Valley and Bay Area will likely see significant changes in weather as well.
"Here's what we know, this will be a major event for the North Bay," said the National Weather Service in its San Francisco area forecast discussion Wednesday.
A high surf advisory has also been issued for several coastal regions, including San Francisco and Monterey Bay, with some waves in the area expected to top 22 feet.
“Dangerous wave action associated with the onset of the strong atmospheric river will result in hazardous swimming and surf conditions the next few days,” the National Weather Service tweeted.
Inexperienced swimmers should remain out of the water due to dangerous surf conditions.
The state has mobilized emergency response teams in seven counties including Ventura, Del Norte, Humboldt, Napa, Butte, Colusa, and Glenn counties. These areas have been flagged because of their vulnerability to heavy rainfall, proximity to burn scars or heightened fire weather conditions.
“We’re now deploying additional resources to counties that are increasingly likely to experience severe weather or mud and debris flow concerns,” Cal OES Fire Chief Brian Marshall said in a statement released by the California Governor’s Office of Emergency Services. “This is part of our commitment to staying ahead of impacts and keeping Californians safe.”
Resources dispatched to these areas include fire engines, helicopters and emergency personnel.
A bomb cyclone occurs when a cyclone rapidly intensifies, or strengthens, over a 24-hour period, according to the National Weather Service.
Atmospheric rivers are channels of high water vapor that carry moisture from the tropics near the equator to the poles, creating high rainfall patterns in their path.
The storm is expected to affect the region through Friday in most places, although some experts say it could last longer in others.
“We have rain in our region’s forecast well into next week, leading into our Thanksgiving holiday,” said Dakari Anderson, a meteorologist at the National Weather Service in Sacramento. He said Californians should plan for moderate to heavy rainfall with the highest amounts expected north of Interstate 80.
Ultimately, Hurley said the best advice is to keep an eye on local weather news and to avoid affected areas, especially those that are experiencing flooding.
“Turn around don't drown. That’s the motto,” he said.