San Onofre State Beach offers consistent surf conditions year-round, with some months standing out as particularly favorable for surfers. The best time to surf here is generally from April to September, when ground swell dominates (90-96% of the time) and wind swell remains minimal (2-6%). During this period, wave quality is reliable, with mean swell sizes hovering around 0.8-0.9m, providing manageable and rideable waves. The downside is that onshore winds (bad conditions) are frequent, peaking at 77% in May, making early mornings or late evenings ideal when winds are lighter. September and October bring slightly improved wind conditions (36-38% good winds) while maintaining strong ground swell presence (89-95%), making them prime months for cleaner waves. Winter months (November-February) see a drop in ground swell consistency (60-74%) and increased no-swell days (16-31%), though February still maintains decent swell size (0.8m). Wind conditions remain challenging year-round, but the fall transition (September-October) offers the best compromise between swell consistency and cleaner winds. For surfers prioritizing wave regularity over wind conditions, late spring to early fall (May-August) is optimal, while those seeking fewer crowds and a chance for better winds should target early fall.