A potent atmospheric river brought heavy rainfall and flooding to the Pacific Northwest in early December, leaving a trail of destruction in its wake. The deluge was triggered by a long band of moisture stretching from the tropical Pacific to the region around December 7.
The phenomenon is an example of atmospheric rivers, which are narrow channels of high atmospheric water vapor that flow like rivers across the sky, carrying water from the equator towards the poles. These events often occur during autumn and winter, but this particular event was notable for its distance traveled – roughly 7,000 miles (11,000 kilometers) from near the Philippines.
Satellite data shows that the region's total precipitable water vapor increased significantly, indicating high levels of moisture in the air. While not all of this moisture falls as rain, it did lead to heavy rainfall totals, with several locations in western Washington exceeding 10 inches (250 mm) over a 72-hour period.
The impact was severe, with river flooding and mudslides reported across the region. The Skagit River and Snohomish River saw record or near-record flood levels on December 11, forcing numerous road closures, including those on I-90 out of western Washington.
In response to the disaster, NASA's Disasters Response Coordination System has been activated to support ongoing relief efforts by the Washington State Emergency Operations Center. Maps and data products will be posted on their open-access mapping portal as new information becomes available.
The flooding highlights the complex interplay between global atmospheric patterns and regional weather events. By monitoring these phenomena, scientists can provide critical insights into extreme weather events like this one, helping to inform decision-making and prepare communities for future disasters.
For those affected by the disaster, it's a stark reminder of the power of nature and the importance of being prepared. The full extent of the damage will only be known in time, but one thing is clear: the Pacific Northwest has faced its share of challenges this winter, and it remains to be seen how long the region takes to recover.
The phenomenon is an example of atmospheric rivers, which are narrow channels of high atmospheric water vapor that flow like rivers across the sky, carrying water from the equator towards the poles. These events often occur during autumn and winter, but this particular event was notable for its distance traveled – roughly 7,000 miles (11,000 kilometers) from near the Philippines.
Satellite data shows that the region's total precipitable water vapor increased significantly, indicating high levels of moisture in the air. While not all of this moisture falls as rain, it did lead to heavy rainfall totals, with several locations in western Washington exceeding 10 inches (250 mm) over a 72-hour period.
The impact was severe, with river flooding and mudslides reported across the region. The Skagit River and Snohomish River saw record or near-record flood levels on December 11, forcing numerous road closures, including those on I-90 out of western Washington.
In response to the disaster, NASA's Disasters Response Coordination System has been activated to support ongoing relief efforts by the Washington State Emergency Operations Center. Maps and data products will be posted on their open-access mapping portal as new information becomes available.
The flooding highlights the complex interplay between global atmospheric patterns and regional weather events. By monitoring these phenomena, scientists can provide critical insights into extreme weather events like this one, helping to inform decision-making and prepare communities for future disasters.
For those affected by the disaster, it's a stark reminder of the power of nature and the importance of being prepared. The full extent of the damage will only be known in time, but one thing is clear: the Pacific Northwest has faced its share of challenges this winter, and it remains to be seen how long the region takes to recover.
Oh my gosh, that's crazy! 7,000 miles of moisture just poured down on the PNW, causing so much destruction 
. I mean, 10 inches of rain in like 72 hours? That's insane 
. My heart goes out to everyone affected by this disaster, it's so sad to see all that devastation 
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Those scientists are working tirelessly to understand what happened and how we can prevent similar disasters in the future 
. And let's be real, those flood maps look terrifying 
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. I mean, have you seen the rainbows that appeared after the storm? 
They're like nature's own art show! And the PNW is already so gorgeous, it's like Mother Nature decided to give us a little present 
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. We got this, PNW! 
I mean, think about it - 7,000 miles of moisture traveling from the equator? That's crazy! It just goes to show that climate change is not just some polarized issue, it's a regional concern too. We need to start investing in those NASA satellite data systems and monitoring stations ASAP 
. And can we talk about the role of global coordination in disaster response? We're already seeing international support from organizations like NASA... why aren't we doing more at home? 
I mean, 7k miles is crazy! It's like that moisture just came out of nowhere 
. I live here in WA state, not too far from Seattle, so we got hit pretty hard. I'm glad NASA is on it tho, they're always good with the info 
. But seriously, it's wild to think about how all those miles of air can bring that much water 
. The roads are still closed, and I know some ppl lost their homes... 
My heart goes out to them. This winter has been pretty rough already, but I guess we're just gonna have to get used to it 
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anyway, i'm glad that NASA is there to help support the relief efforts, but at the same time, it's super frustrating when u think about all the people who lost their homes and livelihoods because of this flood 
flooding everywhere!! 7000 miles of moisture brought all that water & it was so devastating! i feel for those ppl who lost their homes & businesses... the rivers are still swollen 
we gotta be prepared for this kind of thing & support each other during times like these 
Still, I guess it's good to have them on board.
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. It was always going to happen if we didn't take care of the planet.
And I'm glad NASA is there to help with the response efforts 
... its just one of those things where you gotta tip your hat to nature for being so powerful 
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7,000 miles is crazy, I'd get lost on that route. And the rain? Forget about it! I'm talking "let's-go-buy-gloves-and-umbrellas-now" level. But you know what they say, "you can't control the weather, but you can control how you prepare for it"... or something like that 
. Seriously though, the Pacific Northwest is known for its weird weather, but this is on another level! I heard some places in Washington got more rain than a Netflix subscriber gets views 
i can only imagine the damage and disruption it must have caused. does anyone know if the relief efforts are really helping or is it still a mess over there? 
Can't we just rely on good old-fashioned forecasting instead of relying on some fancy satellite data to tell us when a flood is gonna happen?