One researcher expects the polar vortex to strengthen in the next two weeks. This has a huge impact on our daily weather in the Great Lakes region and even the Northeast.

Judah Cohen, director of seasonal forecasting at Verisk Atmospheric and Environmental Research, has been studying the polar vortex for years. He is my go-to meteorologist when the polar vortex looks like it’s moving.

Cohen says the models he relies on show the polar vortex gradually wrapping up tightly over the next two weeks.

The polar vortex is a counterclockwise rotating area near the top of the atmosphere, usually centered near the Arctic region. This fast-spinning vortex is about 50,000 feet high in the atmosphere.

You might think that a strong polar vortex brings bad winter weather. Cohen explains that it’s actually the opposite. Once the vortex gets stronger and starts spinning faster, it actually sucks in the cold air. Cold air is compressed around the North Pole.

The model forecast below runs through mid-November. Notice that the black lines, which are basically wind lines, are tightly packed. This is a sign of increased wind speed and faster circulation of the polar vortex.

With the polar vortex strengthening next week, Judah Cohen says the next two weeks will be fairly mild in the Great Lakes region and the eastern U.S.

“It looks difficult to get any meaningful cold or snow in the first half of November, and probably even in the second half,” Cohen says.

Even if there is a strong polar vortex, we might still get a cold day or two, but we won’t get a cold outbreak that lasts for weeks.

We talk a lot about the jet stream and how it drives storms around the world at our latitude. Pay attention to the jet stream forecast below. You’ll notice a really wavy pattern next week. Swirlings in the jet stream are individual storm systems. These storm systems next week should bring helpful rain to Michigan. However, as we enter the second week of November, the jet stream is also becoming more uniformly circular. This is a sign that the powerful polar vortex is capturing the air beneath it and causing it to spin in unison. The jet stream will not have a major bend in mid-November and will not yet provide prolonged cold.

Cohen says he was able to predict the strength of the polar vortex about a month later. He thinks there are some signs of the polar vortex weakening in the second half of November. If the polar vortex weakens by the end of November, some of the pent-up cold in the polar region may thaw. But Cohen says this didn’t happen right away. He says it could take a few weeks for the Arctic cold to wear off.

This means temperatures probably won’t drop much below normal until at least early December. Cohen isn’t sure the cold will happen then, but he is confident it won’t happen before December.

Cohen also watches for what he calls “polar vortex disruptions.” This is when the polar vortex slows its rotation and its shape becomes truly irregular. Cohen found that the severe cold of the Great Lakes and much of the East Coast came within weeks of these polar vortex disruptions. Some winters experience several major polar vortex disruptions. Some winters experience only one weak polar vortex disruption. This is one of the factors that causes winters to be harsh or mild in the eastern United States.

Cohen doesn’t know when the first full-fledged polar vortex disruption will occur this winter. I’ll let you know when he starts talking about polar vortex disruption. Then you’ll have a few weeks to find your warmest winter clothes. For now, polar vortex disruption is nowhere to be seen.