The highest part of the weather atmosphere is currently undergoing major changes. Researchers find that these changes, which occur high in the sky, eventually turn into a weather pattern here on Earth.
The second part of the Earth’s atmosphere is called the stratosphere. It lies on top of the troposphere, this is where most of us occur again. A Sudden Stratospheric Warming (SSW) is currently underway.
The stratosphere is about 100,000 feet above the ground. Usually in winter there is a vortex centered over the North Pole, with the vortex in the stratosphere. This is the vortex that most researchers call the Polar Vortex. On December 25, the temperature average in this vortex began to warm. Since then, the temperature has warmed to about 100,000 feet 54 degrees Fahrenheit. Although this is an SSW you would think, there is actually another investigation into the weather function.
Michael Ventrice, Ph.D., and IBM meteorologist, say the true key indicator is when the whirling winds of the stratospheric vortex slow down and reverse direction. Ventrice originally studied tropical meteorology and how atmospheric waves across other parts of the world affect hurricanes in the Atlantic Ocean. Ventrice was in school for meteorology in 2012 and says Sudden Stratospheric Warmings was just discovered then. He believes that understanding the stratospheric polar vortex and Sudden Stratosferic Warmings will be the key to issuing a more accurate sub-seasonal forecast. A sub-seasonal forecast is a forecast of 30 to 45 days.
Wind flow and temperature deviation average about 100,000 feet. Large red and white area indicates the area of stratospheric heating
Ventrice explains to us how the domino effect proceeds during and after an SSW. The swirling vortex slows down and the normal westerly wind that turns high above the North Pole becomes an easterly wind. The vortex, called the Polar Vortex, then slides away to be over the North Pole. At this point, Ventrice says where the vortex has moved, the key to the weather in the eastern U.S. in the next few weeks. This SSW has the polar vortex initially centered on Siberia.
The temperature deviation is forecast to reach 100,000 feet higher on January 15, 2021.
Now we start talking about the accompanying weather in the weather atmosphere, the troposphere and here on earth. As soon as the stratospheric vortex moves to Siberia, a strong, deep storm system develops over the North Pacific. The strong storm systems dominate and bend the jet stream over North America. The jet stream comes from the Pacific storm and runs across Canada, replenishing the cold air in northern Canada. Ventrice therefore says that the first effect of this SSW is a hot spell in the eastern United States. This is the hot magic we are currently in in Michigan and the Great Lakes. It’s not very hot, but we walk five to 15 degrees warmer than normal. After a week or so, the strong storm in the North Pacific is replaced by a strong high pressure ridge. Cold air is starting to build up in western Canada. Then the domino effect bends the beam current south over the eastern US. Ventrice says about two weeks after this SSW, colder air should move to the eastern U.S.
Forecast of the steering flow of the weather (about 15,000 feet higher) for January 11 to January 15 shows that colder flows are developing over the eastern United States (graphically thanks to Judah Cohen-AER, a company of Verisk)
All of the weather models we include by meteorologists, including Ventrice, show a somewhat colder pattern around mid-January.
Deviation of the surface temperature deviation for 11 January to 15 January (graphically thanks to Judah Cohen- AER, a Verisk company)
But will the cold be severe and long lasting? Ventrice’s research shows that a sudden warming of the stratosphere begins to Siberia, the subsequent effects on Michigan and the eastern United States are short-lived. He finds that the cold usually lasts a week or so, and then he can return to a warmer than normal pattern. Ventrice says that this back-and-forth cold to warm weather pattern can go through two or three cycles. This would give Michigan and the eastern U.S. a temperature pattern until mid-February.
Ventrice found a worse, prolonged cold pattern when the SSW began crossing the North Atlantic.
Another thing Ventrice is watching to predict the severity and duration of the cold in the eastern United States – an air block over Greenland. A strong block on the upper level over Greenland improves the southern bend in the jet stream over the eastern USA. A Greenlandic bloc is currently expected, but not to a very strong extent.
What does all this mean for Michigan?
The key point here is that the atmosphere is going through some important changes now, and in the next few weeks. That should give Michigan and the eastern U.S. our first blast of true winter cold. Does it bring snowstorms? It’s just hard to see yet, but cold is needed for blizzards. So the first piece of a winter mystery will probably be in place by January 15th to January 18th.
Ventrice suggests that the next research route is to learn how to quantify the amount of cold and the duration of the cold after this sudden stratospheric heating. Ventrice reminds us that this is a relatively new prediction technique for long distance predictions.