The propagation of wind-generated near-inertial waves (NIWs) is well-documented in anticyclonic eddies (ACEs), but remains rarely reported in cyclonic eddies (CEs). Here, subsurface mooring observations in the northwestern Pacific captured two distinct NIW packets (WP1 and WP2) generated by Typhoon Sanvu within a CE. In the typhoon’s wake, WP1 was confined to the upper 80 m, with little energy penetrating deeper despite strong wind forcing. A linear internal wave model and ray-tracing experiments suggest that the shallow mixed layer and the repelling effect of the CE favor lateral propagation of near-inertial energy rather than downward penetration. About two weeks later, WP2 emerged at 450–900 m depth with a velocity amplitude of 0.3 m/s and persisted for nearly one month. Wind work and WKB-scaled near-inertial kinetic energy indicate that WP2 was decoupled from local surface energy and unrelated to WP1. Spectral and modal analyses show that WP2 had the characteristics of low-mode and long-range-propagating NIWs. Ray-tracing and dynamical analyses suggest a plausible remote-source interpretation for WP2, in which it may have originated from a remote cyclonic region 250–350 km away and reached the mooring along a pathway modulated by mesoscale eddies. However, because the present analysis does not resolve the wave packet’s horizontal extent, spatial inhomogeneity of NIW energy may also affect the mooring observations and thus the interpretation of the decay of WP1, the later arrival of WP2, and the apparent lack of downward-moving energy between them. These results highlight the complexity of NIW propagation in eddy-rich environments.
 

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