In reply to Kevster:
In theory it's not a stupid idea. In November, irrespective of what sunshine there may be, temperature, wind direction and wind chill will always be the crucial factors to take into account, as will sea state. Seepage will be an issue too, especially this year. It also obviously depends on which part of Gogarth. The Main Cliff, Wen Zawn etc might simply be too sunless and therefore too cold especially if there's a good breeze blowing. The Upper Tier might be a better choice but, in November, Castell Helen would be at the top of my list provided there isn't a strong south-westerly wind and a big swell. Even then, Where Puffins Daren't or Castell Helen Girdle may be doable. Red Wall and Mousetrap Zawn can be a bit more sheltered than Castell Helen. I once did Lighthouse Arete, Blanco and Mousetrap on a nice early December day.
Choice of route and weather on the day will be critical. If all else fails, there's always Holyhead Mountain, but this suffers from seepage, is rather exposed and multi-pitch it most definitely is not.
Some food for thought if nothing else.
Dave