'Weather bomb' sparks chaos in Scotland

Friday 09th Dec 2011 by theWeather Club

The worst of the weather was not yet over yesterday before the photo that will become an enduring image of Scotland's storms was going viral: a 100m wind turbine, engulfed in flames as it bears the brunt of the gale.

According to the trade association Renewable UK, incidents like this are extremely rare. Yet if the hurricane-force winds that battered Scotland and much of England yesterday proved too much for machines built for windy weather, how on earth did the rest of the country survive in what is technically called 'an explosive deepening'?

The answer can be seen in the scores of photos, videos and stories that are appearing in the relative calm that has since followed, from upturned vehicles to hairy landings at Edinburgh Airport. In Scotland, enhanced contingency planning following last year's snow-based disruption meant warnings were issued in their thousands, closing schools and prompting the shutdown of almost all public buildings. In the Hebrides, Northern Ireland, East Yorkshire and even some parts of the Channel, ferries and train services that weren't cancelled were delayed. And as the air pressure across the Atlantic plunged ever more steeply on Wednesday night, the Met Office issued the highest possible warning for the many densely populated areas of Scotland which they believed would be affected.

Among meteorologists, this phenomenon is known as a 'weather bomb' - although 'explosive deepening' is its more formal title. It occurs when the atmospheric pressure drops more than 24 millibars in 24 hours. On Thursday the air pressure fell by 44mb, and the wind speeds were duly ferocious. Atop the Cairngorms in Ayrshire top speeds of 165mph were recorded. The highest ever is 173mph. As Jonathan Powell, senior forecaster at Positive weather Solutions, told the Telegraph yesterday: "These gusts are really off-the-scale, and surpass hurricane-force. The criteria for what we have seen would fit the weather-bomb scenario."

Today Scotland and northern England are expecting some respite. Forecasters expect the worst winds will remain in the Shetland Islands. Yet the communities affected by yesterday are meteorological battering looks set to suffer for some time after the storm has abated. Last night some 50,000 homes across Scotland were believed to be without power. In Aberdeenshire, several schools and roads are still closed. And in Lancashire, several hundred miles south of the border, the Fire and Rescue Service was called out when the gable end of a house collapsed yesterday evening. Still at £2 million a turbine, the biggest bill will probably be appearing at the unlucky wind farm in North Ayrshire.