Judah Cohen is watching polar vortex weather in Early November that could rewrite the record books. The MIT research scientist said the event is one of the most surprising behaviors he has ever witnessed from the polar vortex, with winds around the Arctic slowing fast enough to raise the chance of a reversal by Nov. 4 or 5.
If that happens, the disruption would beat the previous seasonal record of around Nov. 28 by roughly three weeks. For weather and climate records, Cohen said, "For weather and climate records, that is really unheard of".
MIT and the Arctic winds
The polar vortex is a massive circulation of strong winds spinning around the Arctic high above in the stratosphere, about 10 to 30 miles above Earth in the stratosphere. When it is strong and stable, it tends to keep the coldest Arctic air closer to the pole. When it weakens, stretches, or splits, it can reorganize the jet stream and send pockets of frigid air south.
Forecasts now show the winds surrounding the vortex slowing dramatically. They could reverse direction completely during the first week of November, and the same forecast points to a possible split into two main sections.
Rossby Waves in Early November
The upper atmosphere is experiencing sudden stratospheric warming, with temperatures able to surge as much as 50 to 70 degrees in a couple of days high in the sky. Large-scale pools of warm air have drifted north and propagated vertically through the atmosphere, and scientists refer to those pools as Rossby Waves.
Rossby Waves can crash into the polar vortex and cause it to weaken and sag. Statistically, the overwhelming majority of Rossby Waves usually occur during January and February, which is why Early November stands out as unusually early for this kind of disruption. Cohen called the event, "It is one of the most, if not the most surprising events or behaviors I have ever witnessed from the polar vortex".
New England and El Niño
A very strong El Niño usually makes the polar vortex more stable heading into winter, but this setup points the other way. New England could feel the effects if the disruption changes how the jet stream organizes cold air, although that does not mean cold air would spread everywhere at once.
The practical question now is whether the winds actually reverse around Nov. 4 or 5 and whether the vortex split holds. If it does, the early disruption would set a new record dating back to the 1950s and give forecasters a rare November signal to watch as winter patterns take shape.
