I’ve been going through a number of the different computer models and Medium Term Teleconnections and there seems to be good agreement for a reload of cold weather towards the middle of the month. After a slightly less cold couple of days across Southern Areas High Pressure looks likely to build Northwards into the Atlantic allowing cold Northerly winds to develop this week, it then looks like High Pressure will shift South-Eastwards across the United Kingdom keeping things cold and settled, it’s beyond then things become a little more interesting.
The chart above shows us the different ensembles, each line represents a different ensemble member and we use this to see how much support we have in the longer term for a certain pattern. This chart at the moment is showing increasing support for a return to colder weather from the 15th December onwards, we then take a look at the Arctic Oscillation to see what thats showing
The chart above shows us the Arctic Oscillation, typically when its in a negative phase, we see high pressure building across the Arctic and as you can see, the forecast is generally showing it to remain in the negative and along with the ensemble members, this tells us that there is increasing support for High Pressure moving North-West towards the United kingdom bringing a reload of much colder air from around the 15th onwards. Until then, it looks likely to remain cold with high pressure never too far away but the risk of snow, at least for the time being is generally low away from Northern areas.