Nazaré, Portugal, is renowned for its massive waves, particularly during the winter months when powerful ground swells dominate. The best time for experienced surfers seeking large, clean waves is from November through February. During these months, ground swell prevalence is extremely high (77–92%), with mean swell sizes ranging from 2.2m to 2.5m. However, wind conditions are less favorable, with bad winds (onshore or cross-shore) occurring 60–64% of the time. Despite this, the sheer size and consistency of the swells make these months prime for big-wave surfing. From March to October, conditions become progressively less consistent, with a notable drop in ground swell dominance and smaller waves (1.4–2.2m). April to August sees the highest proportion of wind swells, which are generally less powerful and less desirable for Nazaré’s iconic surf. September and October offer a transition period with improving ground swells (47–66%) and slightly better wind conditions (39–40% good winds). While summer months (June–August) are less ideal for big waves, they may still attract surfers comfortable with smaller swells, though wind conditions remain mostly unfavorable. For serious surfers targeting Nazaré’s legendary waves, the winter season (November–February) is the peak window, despite the frequent onshore winds, as the raw power and size of the swells outweigh the wind drawbacks.