Met Office used computer to map storm before it happened

Four days before the storm had taken shape, Met Office was able to accurately predict its size and path using a £30million computer.

14:10 28 October 2013

The Met Office’s £30million supercomputer, which is capable of 100 trillion calculations per second, successfully predicted the size and path of the St Jude’s Day storm four days before it had formed. It used calculations from millions of sites around the world to simulate the weather.

Dan Williams, Met Office spokesman, said: “The accuracy of it these days is enough to pull out factors that could lead to the storm that we saw last night.

“There were factors that played a role in that, there were two weather systems over the Americas which coalesced in the western Atlantic forming a fairly innocuous area of low pressure.

“But then because we have a particularly strong jet stream at the moment it rattled across the Atlantic fairly quickly and it was at that point just off the South West of the UK that we could see there was an area of particularly warm air that was going to be there just as that low pressure reached the UK.

“Those two things combined meant that this low pressure rapidly deepened just off the coast of the UK and energised it, making it much more vigorous and giving it the power it then took across the UK.”