The Met Office can predict whether winters are likely to be cold or stormy a year in advance, thanks to a breakthrough on its new supercomputer.
The long-range forecasts will give the government 13 months to plan flood defences, grit and anti-freeze supplies and will allow hospitals to prepare for spikes in respiratory illnesses during cold winters.
Nick Dunstone, the climate scientist who led the research published in Nature Geoscience, said the forecasts rely on modelling of a climate phenomenon previously thought to be too chaotic to forecast.
The North Atlantic Oscillation (NAO) determines whether the UK will be bathed in milder, wetter weather fronts from the west or colder, drier conditions from Eurasia. It is based on the difference in pressure between the