October is the best weekend of the Welsh year, and the reason is the shape of the land rather than the size of the swell.
Llangennith faces west and wants a westerly swell with an easterly wind. Langland, twenty minutes south, wants a south-westerly swell with a northerly. Those two sets of conditions almost never happen together, and in October the weather is unsettled enough that one of them is happening most weekends. The pair are rarely good together and rarely bad together either, which through the summer is an academic point and in October is the plan: check the chart on Thursday, and one end of the peninsula will have your day on it.
The rest lines up behind that. The autumn lows are properly arriving, the water is still at 15°C, the school holidays are over and there is daylight until seven. Nothing about November or January improves on any of that except the size.

