The weather – and the British obsession with talking about it – has been puzzling outsiders for decades.
Several features of Britain's geography make the weather the way it is: mild, changeable, and famously unpredictable. Britain's position at the edge of the Atlantic places it at the end of a storm track – relatively narrow zones over oceans that storms travel down, driven by the prevailing winds.
As the warm and cold air fly towards and over each other, the earth's rotation creates cyclones. Then there is the Gulf Stream, which makes the British climate milder than it should be, given its northern latitude, and the fact that the UK is made up of islands, meaning there is a lot of moisture in the air.
Many of the day-to-day conversations British people initiate about the weather, however, are mundane. Comments like “cold, isn't it?” don't even particularly demand a full response; a grunt of agreement will suffice.
Weather talk is a kind of code that we have evolved to help us overcome social inhibitions and actually talk to one another.
In some situations, weather talk is an icebreaker. In others it's used to fill awkward silences, or divert the conversation away from uncomfortable topics. We can also use weather speak to gauge other people's mood.
Of course, these kinds of purely social conversations also occur in other cultures. But both the nature of the conversation – and their content – will vary. A country like Britain will choose a safe and personally unobtrusive topic – such as the weather.