With so much cold air spilling into Canada and warmth over the SE USA I can see little in the way of blocking over the Atlantic with so much energy entering it. There is signs of some significant blocking mid month over the arctic which could herald a pattern change but it's going to be difficult to achieve a significant cold spell.
Very mild and wet first half, cold zonality at times but a poor month. The northern hemisphere anomaly patterns resemble January 1994 and December 1989
I'll go for a CET of 5.5C