Rain in the Scottish uplands © Mark Hamblin/2020VISION
Why is the UK so rainy?
By Jonathan Vautrey, a Meteorologist at the Met Office.
How rainy is the UK?
We’re certainly used to a rainy day here in the UK. It can sometimes feel as if Mother Nature has placed a never-ending rain cloud overhead. You would be right to think the UK receives more rainfall than many other countries – we’re one of the rainiest in Europe. The wettest spots of the UK can see four metres of rain in an average year, which is the height of an African elephant! These sites are found in mountainous regions across the west of the UK, such as Eryri, the Lake District and the Scottish Highlands. The mountains also help to shelter the regions behind them. That means those in the east typically receive half the amount of rain that falls across counties in the west.
Woodpigeon © Jon Hawkins - Surrey Hills Photography
Why is it so rainy?
Weather systems around the UK usually travel from west to east. We often see them developing in the Atlantic Ocean before moving towards Europe. This means the UK is one of the first land areas they encounter on their journey. Much of the rain they bring falls across the UK, then the system weakens as it moves further into the continent. This also explains why western areas of the UK are wetter than the east.
Why do weather systems travel in this direction? We’ve got the ‘jet stream’ to thank for that. This is a fast-flowing ribbon of air high up in the atmosphere. It helps to guide the weather systems towards the UK.
Snake's-head fritillary © Guy Edwardes/2020VISION
Will climate change affect UK rainfall?
Climate change is already having visible effects on the world and in the UK. This includes changing rainfall patterns. Rising temperatures result in a warmer atmosphere. Warmer air can hold more moisture. Therefore, when rainfall events occur, they are producing more rain. All areas of the UK receive more rain on average now than they did 50 years ago. We particularly feel this during the autumn and winter months, where climate change has made UK storms 20% more intense in terms of the amount of rainfall. Increasing rainfall will have notable impacts. Flooding will become more likely, bringing a greater risk of damage to buildings. Some crops may become harder to grow due to the wetter winters.