December 1 marks the beginning of meteorological winter. However, there has been a dramatic rise in temperatures at high altitudes above the North Pole (a stratospheric warming event), which will affect the winter weather in Europe and the United States. Blasts of Arctic air may be pushed over to Northern Europe, due to which exceptionally cold conditions may prevail in those regions. Below are some weather patterns you can expect to see this winter:

Northeastern snowstorm

The northeastern snowstorm pattern or the negative phase of the North Atlantic Oscillation causes a dip in the jet stream, due to which heavy snowfall may occur over the East Coast.

Arctic express

The Arctic air will move out of the south of Canada, causing a drop in temperature and the coldest of air to blow in the U.S.

Atmospheric river

California, Washington, and Oregon can expect to witness the impact of the atmospheric river, which is when moisture travels from the tropics or subtropics and causes lots of rain and snow.

Ice storms

The middle part of the U.S. can expect to see ice storms as the jet stream fights to separate the cold air from the warm, moist air. These ice storms can be massive and can go up to a hundred miles.

Lake-effect snow

The lake-effect snow pattern is when rounds of cold air travel from Canada and cause severe snow events.

Given the unusual stratospheric warming event, the polar vortex (an air circulation around low pressure that behaves as a repository for some of the planet’s coldest air) may be affected. If the polar vortex remains stable and strong, the Northeast and the Mid-Atlantic may receive lesser snow as the air will remain suppressed over the Arctic. However, if the polar vortex weakens, it may split and cause some of the coldest weather conditions.