Are we now threatened with the winter of the century? That's behind the forecast!

Are we now threatened with the winter of the century? That's behind the forecast!

Winter is just around the corner, and while many are preparing for freezing temperatures and possible snowy days, a winter of the century may be on the horizon. The polar vortex is responsible for this tendency, a central element of atmospheric circulation, which forms at altitudes of 30 to 50 kilometers and reaches its strongest expression in the cold months. The polar vortex has a direct impact on the weather in mid-latitudes, but its strength can vary and is influenced by the interaction of various factors, such as solar radiation and ocean currents. For example, a stable polar vortex causes cold air to remain in the polar regions, while a weakened vortex can promote outbreaks of cold air into the mid-latitudes. Nevertheless, a weakening of the polar vortex does not automatically mean a cold winter in Germany, as [HNA](https://www.hna.de/welt/hinter-der-wetter-prognose-droht-jetzt-der-jahr Jahrhundertwinter-das-steckt-zr-93982907.html) reports.

Another exciting phenomenon that influences weather forecasts is sudden stratospheric warming (SSW). These events, known since 1952, occur in the stratosphere of the Northern Hemisphere, particularly in the winter months, and can lead to massive restrictions on the polar vortex. Richard Scherhag, a Berlin meteorologist, coined the term “Berlin Phenomenon” for the first documented SSWs. The temperature in the lower stratosphere rises by more than 50 Kelvin within a few days, which reverses the westerly winds into the easterly and is often accompanied by increased cold in Central Europe.

Influences on the weather in Central Europe

The interactions between the North Atlantic, the troposphere and the stratosphere play a crucial role in the frequency of these sudden warmings. Analysis over recent vintages shows that such events occur on average every two years, and that the frequency increased significantly in the 2000s. A total of 37 sudden stratospheric warming events were observed between 1958 and 2019, with a particular concentration in the last two decades. These changes, including the reversal of westerly winds and the associated cooling, can influence the North Atlantic Oscillation, which in turn is crucial for winter temperatures in Central Europe, as Wikipedia describes.

Currently, an Omega weather pattern suggests that weather conditions will change in October. These special weather constellations can already indicate an impending cold winter, even if the exact forecasts are currently uncertain. Conclusion: The polar vortex and possible sudden stratospheric warming remain essential factors when it comes to predicting winter. Ultimately, despite all the meteorological expertise, no one can say with certainty what the weather situation will be like in the near future.