(C) Daily Kos This story was originally published by Daily Kos and is unaltered. . . . . . . . . . . Major Warming Disrupts Polar Vortex: Cold West, 6 Weeks of Extreme WX for U.S. Ahead [1] ['This Content Is Not Subject To Review Daily Kos Staff Prior To Publication.', 'Backgroundurl Avatar_Large', 'Nickname', 'Joined', 'Created_At', 'Story Count', 'N_Stories', 'Comment Count', 'N_Comments', 'Popular Tags'] Date: 2023-02-17 The polar vortex has been disrupted, with a reversal of winds in the mid to upper stratosphere, by a major sudden stratospheric warming. This polar vortex event will have major impacts on the late winter and early spring weather across the northern hemisphere. A major sudden stratospheric warming is underway, causing winds in the upper stratosphere around the pole to reverse. The upper half of the polar vortex has been shoved aside and ripped apart by a hot high pressure area that was generated by an influx of heat from atmospheric breaking waves and eddies. This major warming was preceded by lesser warmings and vortex stretching events, one just before Christmas and one in late January. The first vortex stretching event was associated with the extreme Christmas eve cold air outbreak that caused deadly record breaking snowfall in upstate New York. The late January event was associated with the low level polar vortex displacement towards southeastern Canada and record low temperatures (-47ºF) and wind chills (-108ºF) on Mt Washington, New Hampshire. According to Dr. Judah Cohen an increase in vortex stretching events is associated with climate change and the loss of sea ice in the Barents sea region. Numerical weather models are predicting that more extreme weather will be following this major sudden stratospheric warming. x I do think to understand the relationship between the predicted long duration #polarvortex disruption & the possible impacts on our weather some outside the box thinking (not found in the scientific literature) is needed for the event. Blog is now public: https://t.co/Gg8N2KHLUk pic.twitter.com/zpc33bhrFP — Judah Cohen (@judah47) February 15, 2023 x Preliminary model analyses indicate that a major sudden stratospheric warming (SSW) occurred today, February 16th. This is a displacement event, with the stratospheric polar vortex nudged off the pole. Now we wait to see how it might influence weather patterns in the next 6 weeks pic.twitter.com/ebmvJozHQM — Dr Simon Lee (@SimonLeeWx) February 16, 2023 x Ongoing #PolarVortex disruption is unusually long starting with minor sudden stratospheric warming (SSW) in late January, major SSW in mid-February & double dip in late February. But what has been missing is translation of event impacts to the surface. Will that change in March? pic.twitter.com/9srIjdZiVo — Judah Cohen (@judah47) February 17, 2023 The physics of interactions between the upper stratosphere and the lower atmosphere and upper ocean continues to be investigated by academic researchers. It is not settled science and my understanding of it as a PhD in geochemistry with a background in geophysics is limited. That said, an extreme positive anomaly in ocean heat content in the seas close to the pole on the Atlantic side is one probable root cause of an increasing number of polar vortex stretching events. But what does this all mean for the weather for the rest of the winter and for the early spring? It takes a few weeks for the impacts high in the stratosphere to work their way down. However, there are already impacts from a large anticyclone of warm sinking air in the middle stratosphere on the Pacific/ north American side of the pole that resulted from the earlier vortex disruption that bought the brutal cold to Mt. Washington. The Aleutian low has been disrupted, the Pacific jet stream split and cold air is moving down from Alaska over the Gulf of Alaska and into the western states. This pattern will intensify with the major stratospheric warming. Expect extreme storms in the west and plains states over the next two weeks. The temperature contrast from the western to eastern U.S. will be shocking. An extremely dangerous temperature contrast will build across the U.S. in late February likely bringing on deadly winter storms. This is the 6 to 10 day European model ensemble forecast ending 27 Feb. The American GFS model forecast for next Wednesday evening should be taken as an early warning of trouble ahead, not a prediction. It has created a mesovortex near the Mississippi, Alabama, Tennessee three state region that would be tornadic if it verifies. I think that it’s a model glitch, but the spin in that little glitch is off the charts according to the forecast sounding. This kind of glitch is not normal. It’s a function of the extremity of the situation. A complex extreme storm system is forecast by the American GFS model to develop in the western U.S. and the plains and the Mississippi valley in the middle of next week. The European model has different details but a similar massive storm coming out of the Rockies, wreaking havoc across the midcontinent region with heavy snow and cold on the northwestern side and extreme warmth and severe thunderstorms on the southeastern side. ECMWF 168hr forecast made 12zFriday17Feb23 An extraordinary temperature contrast will exist across north America with extremely warm air in the southeast and extreme cold in the mountain west and northern plains This has been an extraordinarily variable and unpredictable winter. Polar vortex stretching has played a significant role in the variability. The extraordinary January rains in California followed the Christmas cold outbreak associated with that vortex stretching event. What happened was that Siberian air was pushed out into the Pacific instead of towards China and the Pacific jet stream extended into the California coast bringing storm after storm. This pattern was not predicted by the mid to long range models. It was atypical for a La Niña year. It could be explained but not forecast. This late winter major sudden stratospheric warming will bring on the end of winter and early spring with more extreme and dangerous weather. Forecasting the weather will be a challenge. This kind of variable and extreme weather is what James Hansen predicted. This is climate change. [END] --- [1] Url: https://www.dailykos.com/stories/2023/2/17/2153541/-Major-Warming-Disrupts-Polar-Vortex-Cold-West-6-Weeks-of-Extreme-WX-for-U-S-Ahead Published and (C) by Daily Kos Content appears here under this condition or license: Site content may be used for any purpose without permission unless otherwise specified. via Magical.Fish Gopher News Feeds: gopher://magical.fish/1/feeds/news/dailykos/