Its because all the coldest upper air has been pushed over to Asia. On the flip side its helped us sustain northern blocking but left us with -8 air tops.
Longevity and entrenched cold air should be cooling us down anyway but its again a cache22 this pattern because we could do with better upper temps if were looking at convective easterlies over a toasty north sea. The split strat will take care of all that.
We just need to stay cold and build up some snowcover while we can