As the Ryder Cup gets underway in the very wet and windy conditions forecast by our weather experts, our Chief Meteorologist, Ewen McCallum looks at why wind and rain is so common at this time of year.
“Autumn is well known for its gales as wet and windy weather often strips the colourful leaves from the trees. Less welcome of course are falling branches, or even fallen trees themselves which can severely affect our complex transport network.
With the first real windy period of the year upon us, and just as the Ryder Cup gets underway in rather wet and windy conditions, it might be worth pondering on the question as to ‘why?’ it seems to happen at this time of year.
The simple answer is because of the temperature contrast over our half of the globe. The deep areas of low pressure that you see on a weather map are caused by the differences in temperature between the cold pole to the north of the UK and the hot equator to the south. It is nature’s desire to even out these temperature differences that causes these vigorous systems to form and results in a lot of wind and rain. In the Autumn this temperature difference is at a maximum, as the poles are cooling down rapidly with the onset of winter, while the tropics are at their warmest with tropical storms very frequent at this time of year. So because of this large temperature contrast in the Autumn wind storms are more frequent.
Also in the news:
Ryder Cup 2010: Welsh tourist board not singing in the rain (Daily Telegraph)