The Polar Vortex Isn’t Going Away

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I’d like to nominate polar vortex as Meteorological Term of the Year. It wasn’t too long ago that you couldn’t watch the evening news or visit your favorite online site and not see the term polar vortex. Not only that, but it was usually followed by “and if you think this one is bad (cold) wait until next week!” If there was a comments sections to the article, somebody would invariably ask, “What’s this polar vortex?” while somebody else would comment, “Global warming!”

The first day of spring is less than 10 days from now, yet there's a significant snow storm underway today in the Northeast.

The first day of spring is less than 10 days from now, yet there’s a significant snow storm underway today over the Great Lakes and it will move to the Northeast tomorrow. Yet another storm is possible for the Midwest and Mid-Atlantic by the middle of next week.

How have we arrived in 2014 without already learning of the Polar Vortex (read with deep, booming voice)? Must be some new thing, right? Truth be told, it’s always been there. It’s not a function of global warming or climate change, it hasn’t been caused by the pollution over eastern China and it’s absolutely not responsible for Sharknado! However, there are a few things related to this past winter season that perhaps should’ve shared the media spotlight with the polar vortex. The first would be La Niña and the second would be the pronounced and long-lived North Pacific blocking ridge. Before we begin with those two items, some background on the polar vortex might be helpful.

The Polar Vortex, as we came to know it this past winter, was a brutally cold outbreak of Arctic air, descending from the main vortex while plunging much farther south than usual. Since we’d not heard of it before and it had to do with crazy weather, naturally it was assumed the polar vortex (or, P-vo, as I like to call it) was a new feature and had to be the result of climate change. Alas, it’s not nearly that sophisticated.

Since the world began spinning, there’s been a polar vortex. It looks like the first Wikipedia entry on the subject was in 2005, but the spinning planet predates that by several years. And it’s not a difficult concept to grasp: Put yourself at the very top of the world and stand so you’re facing west. Without any weather system to otherwise alter the wind and assuming no sources of friction like mountains or skyscrapers or trees, you’ll have a wind in your face from the west. That wind is, generally speaking, the polar vortex (Dictionary.com defines polar as pertaining to the North or South Pole and vortex as a whirling mass of air, especially one in the form of a visible column or spiral, [such] as a tornado). That’s P-vo. During the Northern Hemisphere’s winter, when the North Pole is tilted farthest from the incoming rays of the sun and shrouded in darkness, the vortex is at its strongest.

What of the blocking Pacific ridge? That’s the real story. With the strong blocking ridge taking the shape of an amplified Omega, unusually warm air (on warm ocean currents) drifted north. The strong ridge displaced the typical center of the vortex about 10 degrees farther south than normal. And since an Omega block is difficult to displace, it seemed the vortex settled into the new neighborhood with no intention of returning home. On several occasions (and for extended periods) this past winter, Houston was colder than Anchorage and Alaska set records for the third warmest January of all time (since records have been kept). As ImpactWeather’s MarineWatch Manager, Joe Basciani, said earlier today, “What goes up, must come down” — if unusually warm air is moving northward someplace, then there must be unusually cold air moving southward someplace. As it turns out, that someplace was the eastern half of the United States.

In the shape of the Greek letter Omega, an upper-flow pattern such as the one above is difficult to break. Warm air off the mild Pacific easily streamed into Alaska, while frigid air sourced from Siberia and northwestern Canada plunged into the Midwest, the Deep South and the eastern U.S. Image: ImpactWeather

In the shape of the Greek letter Omega, an upper-flow pattern such as the one above is difficult
to break. Warm air off the mild Pacific easily streamed into Alaska, while frigid air sourced from Siberia and
northwestern Canada plunged into the Midwest, the Deep South and the eastern U.S. In the meantime, California stayed unusually dry – another La Nina characteristic. Image: ImpactWeather

And we have to consider La Niña in this broad, global pattern. The cooler-than-normal central Pacific waters which indicate the presence of La Niña, tend to enhance the high pressure over the central and eastern Pacific. In turn, this helps anchor the Omega block.

Without the Omega, the vortex wouldn’t have been displaced. Without the Omega, Alaska wouldn’t have been so warm. Without the Omega, Houston (and so many other places) wouldn’t have been so cold. Without the Omega, California wouldn’t be in the midst of this generational drought – wait, that’s a story for another time.

As for the history of P-vo, why have we not heard of this before? We have actually, if not in name then at least in symptom. For that, we’d have to go back to the 1970s for a similar weather pattern. Like a new generation raised on the coast without ever experiencing a hurricane (and thinking, “No big deal,”), today’s casual weather-watchers aren’t quite as tuned in as they should be before declaring something as “new.” We’d have to go to our grandparents to get the true take on this past winter, and maybe their parents or grandparents for the previous occurrence of the polar vortex and its unusual push southward.

As with many things concerning the weather, rarely is an event truly localized or truly isolated. It’s all global, of which we only see our one small part. The sun, the atmosphere, the oceans are all driving factors that simply can’t dish out the brutal winter to Secaucus in New Jersey, without reversing the situation in, for instance, Homer, Alaska.

Our ImpactWeather team of meteorologists is equipped to see the big picture. Our StormGeo family of companies has 25 offices in 14 countries and meteorological offices in key locations across the globe. Our forecasts for ships, aircraft and onshore facilities have to consider every aspect of any blocking ridge, as well as unusual temperatures brought about by La Niña and/or El Niño. The polar vortex is an intricate and related piece of all the global weather patterns — it’s always been there and it’s not going away any time soon.

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