Forget the confident predictions of HP establishing in the coming week. Instead there's a mixed bag of transient Hp and/or weak ridges with occasional incursions of LP. Both ECM and GFS do roughly agree from the 27th with major depressions in the Atlantic andover N Russia, and HP then developing over the UK, strongly according to ECM, less so in GFS. That is however contradicted by http://www.wxmaps.org/pix/prec4 showing a lot of pptn all across the UK at that time.
And GEFS? For England, dry this coming week, a bit more rain next, temps above average to start with then dropping back. Scotland and NI much more of a scramble with no clear pattern.
Low confidence in all outcomes IMO - keep watching