13th Beach • Statistics for November

November: Fading Groundswell, Building Summer Chop

November marks the return of the summer regime in earnest. Average swell period drops to 11.5s, average wave height eases back to around 5ft (1.5m), and ideal surfing wind falls to 17%. The wave direction is still overwhelmingly SW-SSW - those two directions combine for about 72% of the waverose - but the pulses become less frequent and less powerful compared with winter. The wind story changes dramatically: onshore SSE-SW winds jump to 41.4% of observations, while offshore N, NNE, NE and NNW flow drops to 13.8%. You can almost set your clock by the afternoon sea breeze, which will put chop on the surface and degrade the quality of even a decent 3-6ft (1-2m) groundswell. Water temp is on the rise at 17.3°C, with average air temps of 14.7°C, so balmy conditions are taking over. Sessions in November are doable but increasingly confined to the early morning or to days when a strong high-pressure system keeps the northerlies blowing past noon.