Am I right in saying that as it's been zonal now for several weeks over the the winter solstice period, when above 70N there is no daylight, the cold has been locked in the upper atmosphere of the Arctic, getting colder & colder, with no incursions of real cold in to the more temperate latitudes at the surface?

So as the warm air from the tropics, that is being advected up the western side of the UK by the High Pressure over Biscay into the Artic regions rises through the atmosphere, dislaces the cold Arctic air high in the upper polar atmosphere causing a SST, the now extremly cold & dense polar air sinks to the surface & heads South to replace the void left by the warm air from the tropics that first headed North?