Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ US https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ A Category 5 atmospheric river – stretching 2,700 miles across the Pacific Ocean – has soaked the northwestern United States

A Category 5 atmospheric river – stretching 2,700 miles across the Pacific Ocean – has soaked the northwestern United States



So far this year, Seattle has seen nearly 6.5 “of rain. With an additional 2-4 inch forecast, the city could receive about 25% of its annual rainfall by Jan. 15 from the atmospheric river that soaks the region.

“This soft start could drive Seattle to its only wettest start in any year recorded. The previous wettest period from January 1 to January 1 occurred in January 1956, when nearly 7 inches fell in the first half of the month,” says CNN meteorologist Pedram Javaheri.

Atmospheric rivers are long, narrow areas of the atmosphere – like rivers in the sky – that carry water vapor, according to the National Oceanic and Atmospheric Administration.

This atmospheric river event is classified as a Category 5 – the highest level – from the Center for Western Weather and Water Extremes. The flood potential is huge, with around 15 million people under some kind of surveillance or advice. Parts of western Washington could see 300% of normal rainfall, according to the Weather Prediction Center.
“Soil saturation levels range from 75-95% along the western third of the region right now. It will not take much rainfall to lead to surface flooding,” Javaheri says.
Check the forecast across countriesand

There is also plenty of warmth in the middle of the atmosphere during this particular atmospheric river event. This raises the snow level to heights above 6,000 feet above large parts of the cascades, with rain falling below this level.

“This will further exacerbate flooding problems as heavy rain falls on top of abundant snow. The threat of rapid melting, increased runoff and downstream river flooding is something that everyone in western Oregon and Washington should be aware of,” Javaheri said.

Higher altitudes in Washington could see 2 to 4 inches of rain over the next 24 hours, increasing the risk of flooding and landslides.

Forecast models show moisture - shown in blue - extending thousands of miles.

Precipitation at lower altitudes should be between 1 and 2 inches during this time.

In Portland, Oregon, the National Weather Service Office has predicted up to 7 inches of rain in the higher terrain and up to 2 inches for the lowlands through Wednesday morning. Along with that, there is a warning of strong winds.

Two to four inches of additional rainfall is possible for the Pacific Northwest

Wind warnings stretch along the entire Oregon coast, where gusts can reach up to 75 mph. This raises concerns about fallen trees, power outages and possible hazards along Interstate 5.

The effects of the record-breaking forest fires are also increasing the threat of flooding for Oregon. According to the Oregon Department of Forestry, more than 1 million acres burned. These burning scars that remain make the flood threat even greater due to charred soil with no vegetation to soak up the rainwater. This improves the possibility of flooding and landslides due to the loose terrain.

The sinner

The weather phenomenon that causes all this rain is called an atmospheric river. They are basically rivers with moisture high in the atmosphere. They carry abundant moisture from tropical areas and release it in other areas in the form of rain or snow.

According to NOAA: “These steam columns move with the air and carry an amount of water vapor that is roughly equal to the average flow of water at the mouth of the Mississippi River.”

Not all atmospheric rivers are bad. Many times they carry very beneficial rain to areas that need it. Many areas along the west coast receive 30% -50% of their annual rainfall in just a few such events.

But with a stronger event, it could lead to dangerous flooding and life-threatening landslides. The atmospheric river that stretches from Hawaii to the west coast has been referred to as the “Pineapple Express” and is one of the most famous atmospheric rivers.
A December 2019 study published by researchers at Scripps Institution of Oceanography suggests that atmospheric rivers over the past 40 years have posed a flood risk of $ 1.1 billion. $ For each of these years along the west coast.

This particular atmospheric river has a span of 2,700 miles with a bullfight to the northwest. That equates to the distance from Seattle to Miami when the crow flies, and the moisture it carries could possibly place January 2021 in the record books.

Hurricane hunters find their way to the west coast

This atmospheric river event is so marked that hurricane hunters will fly through it and release buoys.

“To really understand how important an atmospheric river event will be, you have to get close to it. Hurricane hunters fly inside them and collect valuable data, which forecasts then use to determine how a particular atmospheric river will affect the Pacific Ocean. coastal region, “said CNN meteorologist Allison Chinchar.

This is their second seasonal flight, and something they do regularly.

“Hurricane fighters began flying in atmospheric rivers for the first time in February 2016 and have been sending 6-12 flights every January to March ever since. In itself, it is not uncommon for them to fly this event, although it is a popular misconception about , that when the hurricane season wind dies, so does their role, “says Javaheri.


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