A significant disruption to the polar vortex is forecast to occur within days, potentially bringing colder-than-usual conditions to parts of the United States and United Kingdom in late November and early December. Meteorologists warn this could be the earliest major breakdown of the polar vortex on record, based on data dating back to 1959.
The disruption involves a weakening or reversal of high-altitude winds that typically circulate around the Arctic, a phenomenon known as a sudden stratospheric warming event. While this warming occurs 50,000 feet above Earth’s surface, it can indirectly alter the jet stream, allowing Arctic air to push farther south. The National Oceanic and Atmospheric Administration (NOAA) and other agencies have noted that such events do not guarantee extreme cold but increase the likelihood of colder conditions in affected regions.
Forecasted impacts in the US
Forecasters at The Weather Channel and MIT’s Judah Cohen indicate that eastern areas of the US, particularly east of the Rocky Mountains, may experience cooler temperatures starting in late November or early December. A segment of the polar vortex is projected to shift toward Canada, which could further influence weather patterns across North America. However, the exact timing and severity of any cold outbreak remain uncertain, as they depend on how broader atmospheric conditions develop.
Potential effects in the UK
Meteorologists in the UK are also monitoring the polar vortex disruption, raising concerns about a possible repeat of the 2018 ‘Beast from the East’, which brought heavy snowfall and freezing temperatures to Britain. While a weakened polar vortex can allow Arctic air to reach lower latitudes, the final impact on the UK’s winter weather will depend on additional factors, including the influence of El Niño, a climate pattern characterized by warmer Pacific waters. The Met Office has noted that El Niño could interact with the polar vortex disruption, potentially amplifying cold spells in Europe.
El Niño’s role in global weather patterns
The National Weather Service’s Climate Prediction Center reports that El Niño is intensifying and may become one of the strongest on record since 1950. Typically, El Niño brings wetter conditions to the southern US and warmer, drier weather to the northern US during winter. However, its interaction with the polar vortex could complicate these patterns, particularly in regions already vulnerable to sudden cold snaps.
What is the polar vortex?
The polar vortex is a large, circulating band of strong winds that forms high above the North Pole during winter, trapping extremely cold air over the Arctic. When this circulation weakens or splits, it can disrupt the jet stream, a fast-moving air current that steers weather systems. This disruption can allow frigid Arctic air to spill into North America, Europe, and Asia, though the location and severity of any cold outbreak vary based on atmospheric conditions.
Timeline and uncertainty
While the polar vortex disruption is expected to occur within days, its full effects may not be felt until late November or early December. Forecasters emphasize that the outcome remains uncertain, as the interaction between the polar vortex, jet stream, and other climate patterns like El Niño will determine the final weather impacts. The earliest recorded polar vortex disruption occurred on November 28, and this event could surpass that record if it unfolds as predicted.