I am seeing that forecasts continue to enhance my much-anticipated suspicion that we will see a full collapse of the polar vortex, and this could be happening in the next two to three weeks.
We'll go image by image. This first image above is the Day 10 forecast of heights and temperatures. Areas of lower pressure are marked with the letter L, and are also shown with decreasing numbers closer to the center. Warmer temperatures are shown in warmer colors. We can clearly see that the polar vortex is nowhere near organization, a result of several sudden stratospheric warmings (SSW), an event that forces warm air into the stratosphere and increases chances for cold air about 2-4 weeks later. Typically, if we were to find a sturdy polar vortex, there would be a single low pressure vortice centered over the Arctic. However, in the above forecast image, we see three separate vortices of the polar vortex, none of which are close enough to the Arctic for me to determine that they are in control of said area. What I can determine is that the polar vortex is beginning its dramatic collapse that could bring a brutally cold February IF, and ONLY IF the atmospheric pattern cooperates.
If you saw the title of this post mentioning North America and Europe, you may be intrigued. However, if you look towards Greenland and then look east, you will see several arching formations. This signifies high pressure in the area, possibly leading to a negative NAO, which would then enhance cold weather over those areas.
The next image shows the same height forecast and temperature outlook, but now for the 30mb region of the stratosphere, typically defined as the middle-upper stratosphere. Again, we can see a very weak polar vortex split into multiple centers and multiple vortices across this layer of the stratosphere, enhancing the case that the stratospheric polar vortex is on its last leg. I have no doubt that, should this forecast verify, this will be an irreversible act that will prevent the polar vortex from fully recovering for the rest of the winter. We just went through a historic sudden stratospheric warming in recent days, that will take some time for the vortex to heal, if that's even possible anymore. In this case, we see the main vortice over western Greenland, which usually would be a concern for the negative NAO. However, the 30mb level does not have the same effect as the 100mb level in that the 30mb level is too high up to bring about any significant weather changes to the troposphere, unlike the 100mb layer.
Our final image is of the ECMWF's potential vorticity forecast. We see a mostly blue chart with a few colored areas. The warmer colors depict areas of higher potential vorticity, which will denote low pressure areas (in this case, the polar vortex). Blues denote higher pressures, which hamper the polar vortex's formation. In the above image, valid for Day 10, we see a very disfigured polar vortex. There are three separate vortices- one if over north Canada, another over Europe and a third in Asia. The Canadian vortice will act to try and push south into more of Canada and possibly into the United States if the atmospheric pattern allows. The second vortice over Europe will act to enhance cold prospects for the continent for February, as I attested to in
yesterday's article here. The third vortice over Asia will provoke storm systems to begin making a rebound in the US after a recent dry spell over much of the nation, not helped by an ongoing drought in much of the Plains and Rockies.
I'm seeing good indications that the polar vortex is on its way down, and February should end up nice and cool to round out winter. Just how cold is TBD, but things are looking up.
Andrew
