Biarritz, France, offers consistent surf conditions year-round, but the best months for surfing are typically from October through February, when ground swell dominates and wave quality is at its peak. During this period, ground swell percentages range from 66% in October to 88% in January, ensuring powerful, well-formed waves with mean swell sizes between 1.4m and 2.0m. Wind conditions are also more favorable compared to other times of the year, with good wind percentages peaking at 43% in December. The autumn and winter months bring the largest and most reliable swells, attracting experienced surfers looking for powerful, clean waves. Spring (March to May) and summer (June to August) see a decline in ground swell dominance, with wind swell becoming more prevalent. Wave quality diminishes, particularly in summer, when ground swell drops to as low as 19% in July, and mean swell size hovers around 1.0m. Wind conditions worsen, with good wind percentages falling below 30% from April onward, making onshore winds more frequent. While still surfable, especially for beginners or those happy with smaller waves, these seasons are less ideal for advanced surfers seeking solid groundswell and clean conditions. September marks a transitional month as ground swell begins to increase again, setting the stage for the high season ahead. Overall, the optimal window for the best surf in Biarritz is late autumn through winter, when powerful, clean groundswell combines with relatively better wind conditions for high-performance surfing.