The weather phenomenon responsible for the infamous 'Beast from the East' snowstorm in 2018 is showing signs of potentially repeating, according to meteorological forecasts. This event, known as Sudden Stratospheric Warming (SSW), plunged the UK into a deep freeze seven years ago, with some areas buried under 20 inches of snow.
What is Sudden Stratospheric Warming?
Despite its name suggesting warmth, a Sudden Stratospheric Warming event can usher in bitterly cold Arctic conditions. The Met Office explains that SSW involves a rapid temperature increase of up to 50°C in the stratosphere, located 10km to 50km above the Earth. This dramatic warming disrupts the polar vortex, a large area of low pressure and cold air. The disruption can force cold air southwards, altering the jet stream and creating blocking weather patterns that lock in cold and snow for extended periods.
When Could It Happen and What Would It Mean?
Forecaster Nick Finnis of Netweather suggests a significant warming of the stratosphere could trigger an SSW event around November 25 and 26. He notes this is due to warming from the Canadian side of the polar region, which may displace the polar vortex towards northern Russia and north-east Europe.
However, forecasters are quick to temper expectations of a repeat of the 2018 chaos. If the SSW occurs, the UK might see an increased chance of colder and wintry conditions from late November through December. Finnis clarifies that "there are no guarantees of colder weather because of a SSW", but the risk is elevated.
Immediate Snow Forecast for the UK
Before any potential SSW effects, the UK is already braced for wintry weather next week. The Met Office forecasts potential for rain, hill snow, and icy stretches, particularly across northern regions on Tuesday and Wednesday. Similarly, BBC Weather predicts showery rain turning wintry on northern hills, with cold conditions and overnight frosts persisting for many.
