Ryder Cup washout!
Golf can be played in the sun and even in the rain. When the Ryder Cup came to Wales, in October 2010, everyone was hoping for some nice weather, but heavy rain stopped the golfers competing.
Golf washout at the Ryder Cup
Why do we get a lot of rain in Wales?
Over the past few years, Wales has had a lot of bad weather with rain and floods in many areas.
Air carries water vapour in it (that’s water in a gas form). This forms when wind passes over and evaporates some of the Atlantic Ocean to the west.
Air that is high up is cold and can’t hold as much water vapour as low warm air so some of it has to condense. When this happens tiny droplets are formed which we call clouds. When it’s really cold they freeze together and get big enough to fall as precipitation.
Why does it rain more in Wales?
There are oceans surrounding Wales and this causes the air to carry lots of vapour. We also have lots of hills. When we do get warm weather, it pushes the air upwards and this causes convection rain. But, we also have fronts!
What are fronts?
On a map of the world, you can find Wales just over half way from the equator to the North Pole. Because of where Wales is in the world, warm air from tropical regions and cold air form the polar regions meet above us. These different types of air don't easily mix and the boundary between them is called a front.
What is a front?
Fronts were first observed by scientists during the First World War. They got their name because they acted very much like the armies: they were opposing each other, but faced each other along a line of trenches called a front.
They decided the two different types of air were behaving in the same way and so the name has stuck ever since.
An example of a weather front
How do fronts cause rain?
Cold polar air is heavy so it pushes the warm air up and it gets colder. Cold air can’t hold water so it falls down as rain. Wales gets lots of fronts from west to east which causes a lot of frontal rain.
They decided the two different types of air were behaving in the same way and so the name has stuck ever since.
Why do eastern parts of Wales get less rain?
After the air has been forced to rise, it causes relief rain over hilly Wales to the east of the Welsh mountains. The air sinks down, warms up and then dries out. This forms a 'rain shadow' and causes nicer weather as a result.
A rain shadow
