UK Winter Forecast:
December: Displaced Polar Vortex generating high volume of high pressure, resulting in temperatures close to or slightly below the seasonal average. High pressure dominating across Northern areas, leading to generally dry, frosty and cold conditions. The Atlantic always posing a threat of milder weather (fought with a snow risk across Central areas), however weaker than recent years; resulting in drier than average conditions. Any precipitation that does fall is likely to pose a wintry threat, especially later in the month.
January: A Colder, Wetter and Wintrier Month.
January is likely to be dominated by low pressure, bringing cold North Westerly winds, wintry showers and generally fairly wet weather for many areas. At times, winds will rotate to the NE as high pressure builds over Iceland, providing chilly Easterly winds, which increases risk of disruptive weather. Temperature: At or Slightly Below average. Precipitation: Slightly Above Average.
February - Very Uncertain, chances of dominant blocking.
In weather forecasting, long range forecasts are always experimental. However signs are that blocking could become even more dominant this month, giving drier weather than experienced earlier in the winter.
The United Kingdom is positioned on the boundary of major air masses, these air masses interact with each other in a volatile sense, therefore it is difficult to predict long range weather. Further updates will be provided, however a combination of La Nina (jet stream weakening), (and the jet stream provides usual "wet and windy" weather), lower solar activity (sunspot numbers), is causing the polar vortex (an area of very cold air over the pole), to be displaced, this means that for Winter 2016/17, there is a higher risk of cold air sinking south and affecting mid latitude areas.
The jet stream will still have some strength, and is still likely to poise a threat, meaning there will be "cold spells" this winter, and in January, these could be significant. Please stay tuned for further updates, the weather team.