La Nina and Polar Vortex winds are setting up for a harsh winter in the US

Next week’s pre-winter arctic plunge might be a sign of things to come for the Eastern U.S., as several key weather patterns will converge to bring early bone-chilling cold and potentially more snowstorms to the region.

According to the FOX Forecast Center, two weather patterns, La Niña and an easterly Quasi-Biennial Oscillation, will allow more rounds of arctic air that is typically trapped high above the North Pole to spill into the lower levels of the atmosphere and south into the Eastern U.S.

This frigid air is known as the “Polar Vortex.”

Air in the polar vortex sits in the stratosphere, some 10 to 30 miles above the Earth’s poles and intensifies during the winter, when a lack of sunlight cools air at this height to below -70 degrees Celcius.

The polar vortex typically remains locked over the North Pole and Northern Canada as well as up in the stratosphere, separated from warmer air in the lower level of the atmosphere, the troposphere—that makes up the weather we experience.

While the El Niño–Southern Oscillation (ENSO) is typically the driver of most weather, another lesser-known climate pattern, the Quasi-Biennial Oscillation (QBO) will play a big role early this winter.

The QBO refers to the direction winds are blowing in the stratosphere around the equator, which in turn will influence the strength of the Polar Vortex.

The current easterly phase of the QBO will weaken the barrier surrounding the Polar Vortex, allowing that ice-cold air to infiltrate the lower levels of the atmosphere.

Meanwhile, La Niña typically creates more dips in the Pacific jet stream, which will allow that cold air sitting over Canada to spill south into the Eastern U.S.

The FOX Forecast Center has found that years when both La Niña and an easterly QBO were present were much colder than average across the East.

Snow-cember?

While the exact frequency and intensities of snowstorms are impossible to predict, the presence of cold air will turn storms that move across the country from rainmakers into snowmakers.

La Niña also typically brings snowstorms to the Northern Tier during winters, while the southern part of the country typically stays warm and dry.

The upshot is that forecasters are confident that the areas around the Great Lakes in the Upper Midwest and Northeast, as well as New England, will see more snow than usual this December.

Meanwhile, any coastal storms that form in the presence of arctic air will be strong snow-producing nor’easters.

While future storm tracks are uncertain, forecasters are increasingly sure that millions across the East will be reaching for a warm beverage to start this winter.