I've noticed the Met Office is advising a weather advisory for
Saturday morning for the south of England for heavy rain, but that
doesn't seem to tie in with the pressure charts: GFS and ECM suggest
some rain going through Friday night (after midnight, so technically
morning I guess) then some more after dark on Saturday - the Met
Office pressure charts suggest the same but the low moving in from the
SW after dark on Saturday seems to be absent. So where do they get
Saturday morning from?

Nick