Interesting post on Facebook by British Weather Services ( a site I've found to be really good over the years)
https://www.facebook.com/BritWeatherSvs
The UK will go into the fridge freezer from the 21st, snow for large parts of the north , bits & pieces further south. Sudden Stratospheric warming/Polar vortex dislocation being responsible.
One to watch. Model thread getting excited already