Two major storms in a week may have come as a shock, but trouble has been brewing for some time. The Pacific around the equator is in the throes of La Niña, when the seas turn cooler than normal towards South America. Even though thousands of miles away, La Niña often brings a wet and windy end to winter in the UK, with a powerful jet stream driving depressions across the Atlantic. And as the core of the jet stream powered to more than 200mph this week, Storm Eunice rapidly exploded into a ferocious storm. Not only that, but the vortex of winds whirling around in the stratosphere high above the Arctic are unusually strong this winter, helping drive westerly weather across the Atlantic.
When will it all end? The signs are that windy, wet weather could last into March before La Niña weakens and the polar vortex decays. Looking on the bright side, the wet westerly winds are boosting water supplies in many parts of the UK, where it had been unusually dry, and wind power generation has surged this week. And despite the battering from storms, this winter has also been mild over much of the country.
