Record‐Shattering Winter “Heatwave” Over the Antarctic Peninsula in 2026, Associated Primarily With Tropical East Indian Ocean Surface Temperature Anomalies

Abstract Extreme winter warming events over the Antarctic Peninsula (AP) have potential impacts on ice‐shelf stability, but their mechanisms and teleconnections remain poorly studied. Using multi‐station observations, we report several warm extremes during May–June 2026, with early–June temperatures exceeding 0°C and peak anomalies reaching +22.32°C. These extremes were primarily driven by a pressure‐dipole pattern, featuring an enhanced Amundsen Sea Low and Drake Passage blocking, which directed frequent atmospheric river landfalls. The resulting moisture‐heat advection, alongside enhanced downward longwave radiation, dominated the rapid warming over the AP. Notably, record‐high sea surface temperatures in the tropical eastern Indian Ocean played a key role in this anomalous circulation, whereas the concurrent El Niño (still developing) had minimal direct impact. Our findings enrich the rare wintertime cases and identify the tropical Indian Ocean as a key precursor for improving projections of such events, which is also essential for estimating their impact on ice‐shelf stability.