NASA Image Shows Swirling Power of Bomb Cyclone As It Hit Pacific Northwest

A powerful bomb cyclone blustered into the coast of the Pacific Northwest on Tuesday night, leaving hundreds of thousands without power and claiming at least two lives.

Over 600,000 people across Washington were left without power as the storm-force winds hit, with two people reportedly having been killed near Seattle due to falling trees.

NASA has shared an image of the spiral-shaped storm system as it barreled toward the Northwest coast, bringing intense rainfall and powerful winds.

This image was captured by the VIIRS (Visible Infrared Imaging Radiometer Suite) on NOAA's JPSS-1 (Joint Polar Satellite System-1) at 1:50 p.m. Pacific Time on November 19, just before its winds slammed into the coastline.

Image of the bomb cyclone off the Pacific Northwest on November 19. This storm brought powerful winds and intense rainfall, resulting in hundreds of thousands losing power and at least two deaths. NASA Earth Observatory image by Lauren Dauphin, using VIIRS data from NASA EOSDIS LANCE, GIBS/Worldview, and the Joint Polar Satellite System JPSS

A bomb cyclone is a type of intense storm that rapidly intensifies over a short period. These storms occur when the atmospheric pressure at the center of the storm drops by a significant degree within 24 hours, in a process called bombogenesis. This usually happens when a cold air mass collides with a warm air mass, creating an environment conducive to rapid intensification.

"The intensification required to classify as "bombogenesis" varies by latitude. At 60 degrees latitude, it is a drop of at least 24 millibars over 24 hours. At the latitude of New York City, the required pressure drop is about 17.8 millibars over 24 hours," NOAA said.

This bomb cyclone formed over the Pacific and was blown towards the West Coast by the Pacific jet stream, with its pressure dropping by 27 millibars in only six hours, classifying it as a "super explosive cyclone", according to The Seattle Times.

This storm is tied with another storm in October 2021 for the most powerful in about 50 years, and was so intense that the National Weather Service in Medford, Oregon said its ilk only occurred "about once every ten years."

"We will continue making these very high impact events more and more likely until and unless we dramatically reduce the burning of fossil fuels," Mathew Barlow, a professor of environmental, earth and atmospheric sciences at the University of Massachusetts Lowell, told Newsweek.

Wind gusts of up to 77 mph were seen in parts of Washington through Tuesday and Tuesday night, with 89 mph gusts in Oregon and 106 mph in Canada's British Columbia. For reference, winds over 39 mph are tropical storm strength, and over 74 mph, are considered hurricane force. A Category 2 hurricane has wind speeds of between 96 and 110 mph.

An atmospheric river is currently moving towards Oregon and California and is expected to bring more wind and intense rainfall to these states for the rest of the week. The NWS forecasts up to 12 to 16 inches of rain across these regions in the coming days, with wind gusts over 60mph.

"Strong atmospheric river continues to impact northern California with heavy rain and life-threatening flooding through Friday," the NWS said in a Short Range Public Discussion.

"A strong atmospheric river currently impacting northern California is forecast to remain relatively stationary over the next few days and produce an additional 6-12 inches of rainfall over regions with already saturated terrain. The atmospheric river is expected to peak in intensity today, but with moderate bouts of rain lingering through much of Friday and snow levels finally lowering somewhat on Saturday."

This heavy rainfall is expected to cause dangerous flooding, with Flood Watches being issued across Northern California. This rainfall is feared to potentially trigger landslides.

"There will be an increased risk of rock and land slides along roadways. Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations," the National Weather Service Eureka office said in a Flood Watch.

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