Abstract Western North Pacific (WNP) monsoon gyre (MG) events are an important large‐scale driver of tropical cyclone (TC) activity. However, prior studies have mostly focused on case‐specific analyses using a subjective MG identification. There is currently limited understanding of MG variability at interannual and longer time scales. Using spatial‐rotational metrics of the low‐level circulation, this study proposes an objective approach to identify MG events. We identify 221 MG events during the boreal summer from 1979 to 2023. MG events have an average duration of ∼5.7 days and a strong association with interannual TC activity. The interannual variability of MG activity is strongly modulated by tropical central Pacific (CP) sea surface temperature (SST) anomalies, which change the zonal and meridional circulation via inter‐basin interactions. We develop a physical‐empirical model for forecasting MG activity using tropical CP SST anomalies from the preceding summer as well as spring central Asian surface temperatures and North Atlantic sea level pressures.

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