Not quite sure what you are after. The jetstream is the important item for the North Atlantic Tracks. It is quite a complex issue which is why it is hard to predict. There is some explanation here:
http://homepage.ntlworld.com/booty.w...nfo/uppair.htm.
Sorry you will have to copy the link as the buttons do not appear to work.
It is not as simple as the position of the high pressure although the two are interconnected.