By using observation and reanalysis datasets, this study identified an enhanced impact that El Nin similar to o-Southern Oscillation (ENSO)-independent spring Indian Ocean basin mode (IOBM) has on summer precipitation in Xinjiang. We concluded that the dynamic origins of the ENSO-independent IOBM can be explained by the extratropical and tropical pathways observed during 1994-2020. Specifically, a barotropic wave train originated from the North Atlantic and placed the Central Asian region below an anomalously low geopotential height center that persisted from Feb-Mar to May-Jul. In a response, the subtropical westerly jet stream moved southwestward relative to the climatology, which was favorable for anomalous southerly low-level winds to enhance precipitation in Xinjiang. Within the tropical pathway, the water vapor circulation patterns manifested an anomalous cyclone over the tropical Indian Ocean and an anomalous anticyclone over the southern Tibetan Plateau extending to the Arabian Sea, which is a classic baroclinic Matsuno-Gill response to the IOBM. The northward transport of moisture flux from the Arabian Sea, which is associated with the anomalous anticyclone, could bring abundant water vapor into Xinjiang, thus increasing precipitation. A physics-based empirical model was further developed to seasonally predict summer precipitation in Xinjiang. The independent prediction skill (2006-2020) from the empirical model indicated that 56% of the variability in summer precipitation in Xinjiang was predictable one season in advance. Our results highlight the important role that the ENSO-independent Indian Ocean SST play in impacting the climate over arid Northwest China.