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Attaining skillful decadal predictions for the western North Pacific tropical cyclone (TC) emerges as a formidable challenge, mainly stemming from the limited prediction skills of Pacific Decadal Variability (PDV) within the state‐of‐the‐art models. Assessing sixth Coupled Model Intercomparison Project models' retrospective predictions finds that the predictability of PDV transcends the expectations set by raw forecasts featured by constrained temporal skills and low signal‐to‐noise ratio. Employing a refined approach, we selectively identify the models that capture the diverse phases of PDV and subsequently adjust their variances. This tailored approach yields a compelling concordance between the predicted PDV and observation in phases and variances. Anchored in the heightened prediction skill of PDV, we establish a sophisticated statistical model adept at predicting the latitude of TC's lifetime maximum intensity (LMI). The near‐term prediction indicates a sustained poleward migration of LMI latitude by 1.53° during 2020–2027, increasing subtropical East Asia's TC‐related disaster vulnerability in the coming decade. Plain Language Summary: Tropical cyclones (TCs) account for one‐third of the deaths and economic losses from weather‐, climate‐ and water‐related disasters. This ratio tends to be much greater in the East Asia region due to its neighborhood to the busiest TC basin in the world‐the western North Pacific (WNP). However, it is particularly challenging to make skillful decadal predictions for the WNP TC activity due to the limited prediction skill of Pacific Decadal Variability (PDV), the foremost driver for the TC decadal variability. Here, we find that the capacity of the current state‐of‐the‐art climate model predicting PDV can be substantially improved. The improved prediction indicates that the latitude of the TCs' lifetime maximum intensity will migrate poleward in 2020–2027, making subtropical East Asia more vulnerable to TC disasters. The finding has profound implications for disaster prevention and mitigation strategies in subtropical East Asia, offering pivotal insights that can significantly enhance preparedness measures. Key Points: Near‐term prediction of tropical cyclone (TC) activity depends on Models' skills to predict Pacific Decadal Variability (PDV), which is limitedWe substantially improved PDV's hindcast skill and the refined approach predicts a PDV negative phase in the near‐term (2020–2027)The predicted PDV phase implies a poleward shift of location of TC's lifetime maximum intensity, increasing subtropical East Asia's TC‐related risk [ABSTRACT FROM AUTHOR]

Tropical cyclones (TCs) formed in the western North Pacific and South China Sea can undergo rapid intensification (RI) shortly before making landfall in China. Forecasting such offshore RI is a great challenge in operations. In this study the offshore RI events in a sheared environment are examined for TCs that made landfall in China during 1979–2017. It is found that there were only three offshore RI events in a sheared environment, all of which occurred to the south of Hainan Island within the monsoon trough in early to mid-July, coinciding with the termination of the mei-yu season. The specific geographic location and timing of the occurrence of the offshore RI in the sheared environment is associated with the adjustment of the East Asia summer monsoon system when the mei-yu season terminates in the Yangtze River valley. In addition to the adjustment favorable for TC intensification by enhancing the TC–trough interaction in the upper troposphere, this study suggests that two environmental factors also contribute to the offshore RI over the South China Sea in a sheared environment. One is the intrusion of dry air associated with the western North Pacific subtropical high (WNPSH) and the other is the penetration of the water vapor flux associated with the monsoon surge. The adjustment of the East Asia summer monsoon system allows the water vapor flux of the monsoon surge to penetrate the TC circulation and prevents the dry air of the WNPSH from intruding into the TC circulation. [ABSTRACT FROM AUTHOR]