Mild sunny weather returning to Aylesbury Vale in time for the weekend

We’re a week into November, Christmas markets are on the horizon – yet scarves and woolly hats aren’t to be seen in Aylesbury Vale – what’s going on?

Last week, we discussed the important airmasses that affect the weather we see in the UK. The tropical maritime and tropical continental airmasses both bring warmer air poleward from regions around the Tropic of Cancer. But how is it determined as to which airmass affects the UK?

The answer is linked to the position of the Polar Jet Stream. The jet stream is a fast-flowing current of air that blows from west to east around the Northern Hemisphere, extending a few hundred kilometres wide and a few kilometres deep. Situated 7km to 12km above sea level, the Polar Jet Stream is typically above the polar front, the boundary where cold polar air meets warm equatorial air.

Like a river, the jet stream meanders, causing the fast-flowing air to blow northward and southward. These meanders are called Rossby waves and can be significantly sinuous with deep troughs and ridges. Recently, the Polar Jet Stream has been ridging over the UK, allowing the warmer equatorial air to spread across the UK, responsible for our mild temperatures.

Towards the end of the week, a ridge of high pressure will be developing to the southeast of the UK, bringing more settled conditions.

Thursday and Friday will see mostly dry and mild conditions with sunny spells across Aylesbury Vale. The weekend will be mostly dry and sunny throughout, with temperatures approaching the mid-teens.