If you take a look at the BBC weather page and on South Scotland ,specifically:
If the wind is predominately coming anywhere from the North to East, this means large swells building up from the North Sea. This results in large swells hitting the coast and large waves and bad shore diving. Plus the longer the wind has been blowing (in days) the worst the sea state and vis. It needs to be calm or blowing from the South for a week or so to garentee good vis.
Alternatively if the sea is coming anywhere from the South to West then this results in flat calm seas. The wind can be quite strong (blowing a hooley from the land and the sea will be flat calm, as the swels are blown off shore. Obviously the longer the calm spell, and better the Vis.
Hope this helps, and oh its blowing onshore (east) and will do over the weekend moving to comne from the North on Sunday (from the BBC).
ps, also check out the tide times from the BBC website. Very handy for diving and saves a dive from being shallow and having to stumble over the rocks if you tip up at the wrong time.
Wind was Westerly on Monday, and I could see the surface from 12m - perhaps one of the best shore dives I've ever had off St. Abbs. Wind had moved round to the North by Tuesday, and both Eyemouth and St. Abbs were not shore divable - no white horses in the bay, but long slow swell crashing over the harbour wall occasionally.