Are you hoping for a few sunny autumn days? When there’s high pressure, that doesn’t always work out; instead, it stays grey in many places.

However, if you’re out and about in the mountains, you can often enjoy the sun. Often, only the peaks rise above a sea of mist.

The reason for this "unfair" distribution of sunshine is, of all things, the high-pressure system itself: sinking air warms up and can form what is known as an inversion. In this phenomenon, warmer air lies like a barrier layer above the cold air at ground level. This prevents the air from mixing properly.

For everyone in the lowlands and valleys, this means that fog and low-lying clouds often linger. If you’ve had enough of the constant grey skies, you’ll usually have a better chance of sunshine in the mountains.