Ondarreta in Spain offers the best surf conditions during the winter months, particularly from November to February, when ground swell dominates with frequencies above 73% and mean swell sizes ranging from 1.5m to 1.6m. These months also have the highest likelihood of consistent waves, with wind conditions being relatively better compared to other times of the year, though still challenging—good wind days occur around 32-34% of the time. The shoulder months of October and March still provide decent surf, with ground swells at 65% and 76% respectively, but swell size drops slightly to 1.2m-1.4m. From April onward, conditions deteriorate as ground swells decrease significantly, dropping below 60% by April and reaching their lowest in July (20%). Summer months (June-August) are the least favorable, with wind swells dominating, smaller waves (0.8m), and poor wind conditions (bad winds 75-77% of the time). September marks a transition back toward better swell, though still with mixed conditions. For surfers prioritizing quality waves, November through February is the prime window, despite the frequent onshore winds, while summer is best suited for beginners due to smaller, choppier surf.