Abstract This study investigates climate drivers influencing interannual changes in the rapid intensification (RI) ratio of western North Pacific tropical cyclones during July–November from 1982 to 2024. We find a pronounced simultaneous correlation between basinwide RI ratio and the Aleutian Low index (ALI). In high ALI years when the Aleutian Low is weakened, the RI ratio is significantly reduced over the region spanning 5°N–25°N, 135°E–160°E, predominantly driven by enhanced 850–200‐hPa vertical wind shear (VWS). Other commonly investigated RI‐related environmental variables show only small ALI‐driven modulations over the primary focus region of this study. In high ALI years, enhanced VWS is mainly induced by anomalous westerlies in the southeastern part of a broad anomalous cyclone centered in the subtropical central North Pacific. This anomalous cyclone can be further linked to strong wave activity fluxes originating from the AL region and propagating southward into the subtropical North Pacific.

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