Abstract In the Ross Sea, sea‐ice processes such as coastal polynya formation and fast‐ice breakouts are often driven by strong winds associated with storms. In this study, a storm index derived from air pressure and air temperature anomalies observed at 13 weather stations in the Ross Sea region was used to investigate storm behavior between 1964 and 2024. It was found that both the frequency and intensity of winter storms have increased in the southern Ross Sea. Storm activity followed a low‐frequency oscillation in phase with the Southern Annular Mode. Since 2016 the inter‐annual variability in mean winter storm activity has reached unprecedented levels. This increase is reflected in the recent increasing variability in winter fast‐ice formation and breakout in McMurdo Sound, which is documented in this study for the period 2019 to 2024 for the first time, with extensive fast‐ice in calm years and late fast‐ice formation in stormy years.