Expect dry and chilly conditions for now in Aylesbury Vale – but a major weather event could be on the way
and live on Freeview channel 276
For the past couple of weeks, meteorologists in Aylesbury Vale and elsewhere have been focusing on the stratosphere – a region of the atmosphere about 10km to 50km above the Earth’s surface – and the Sudden Stratospheric Warming (SSW) that occurred on February 15.
Since the North Pole sees less solar radiation during winter, temperatures plummet, creating stronger westerly winds in the stratosphere. This circulation of winds around the pole, known as the polar vortex, helps to drive our jet stream.
When a SSW event takes place, rapid warming occurs in the stratosphere, with temperatures climbing by up to 50C in a couple of days. When this occurs, the strong zonal flow from west to east in the upper atmosphere weakens, or can even reverse in direction, disrupting the polar vortex.
A displaced or split polar vortex translates to a meandering jet stream in the lower levels of the atmosphere, potentially creating ‘blocking’ high pressure, and dictates the weather for the UK for long periods.
If the high pressure is located over Scandinavia, then very cold polar air from eastern Europe sweeps into western areas – the infamous Beast from the East in 2018 was as a result of one such SSW event.
We are yet to see what effects this SSW event will have on our weather, as it can take up to three weeks for the implications to become apparent.
But here in Aylesbury Vale the remainder of this week looks to become increasingly settled, dry and chilly, with the potential for overnight frosts.