Atmospheric river, record snow: Extreme weather slams West Coast and Hawaii
The hashtag #SnOMG has been making the rounds this week — and for once it's not an exaggeration. From surprise snow showers in the tropics to snowed-in ski resorts, extreme weather has ruled the week out West.
The extreme weather is due to a powerful Pacific Ocean jet stream pattern. Part of the polar jet stream is angled straight south along the U.S. West Coast from Alaska, driving not only cold, but also a parade of storms southward.
In California, the southern branch of the polar jet stream has collided with the sub-tropical jet stream. The result is an extreme 230-mph atmospheric river, also known as the Pineapple Express, plowing into the coast. It is partially powered by the historic storm now moving away from Hawaii.
It's been a wild few days in Hawaii as the historic storm pummeled the Island chain. Wicked winds gusting up to 191 mph were reported on top of Mauna Kea. For perspective, the highest wind gust reported by monster Hurricane Irma was only 9 mph greater. The storm whipped up waves to 50 feet. Even the locals stopped to check out the surf show.
Meteorologists commonly refer to storms like this as "cold-core," because they tend to have a lot of cold air in the mid and upper levels. That was evident when snow starting flying at the lowest elevation ever reported in Maui: At Polipoli State Park, 6,200 feet above sea level.
Maui wasn't the only tropical palm tree paradise to see the flakes fly this week. A burst of snow on the Las Vegas Strip looked like a brief blizzard.
It did not amount to much. Measurable snow falls about once every five years there.
Snow is also a rare sight for the palm trees of coastal California. This was the scene near Eureka, northern California:
Redding, California, a city that averages only 2 inches of snow per winter, picked up 10-14 inches in less than 24 hours. That's just short of the one-day record snowfall of 16 inches.
So far this winter, Redding has seen more than triple the snow than Boston, Massachusetts.
Seattle has seen its snowiest month in 50 years and the seventh snowiest month on record with 20.2 inches so far. It's not often you hear a ski resort complaining about too much snow, but that's just what's happening at the Summit at Snoqualmie, about 33 miles east of Seattle.
The atmospheric river in California led to high wind warnings, flash flooding along the state's coastline and another round of paralyzing snow in the Sierra Nevada Mountains.
So far this season, the peak of Mammoth Mountain, California, has piled up an astounding 38 feet of snow, the most of any U.S. ski resort. There's more snow to come as the area could see another 8 feet of snow over the next 10 days. It's so much snow the resort says it will stay open through July 4.
People in parts of Tahoe are snowed in with "snow so high you can't see out the kitchen windows," as one witness described it.
