Abstract: Under the conditions of high mining height (7 m) longwall mining in the Shendong mining area, thick and hard roof strata exhibit strong sudden caving behavior, intense ground pressure manifestation, and difficulty in early identification of initial weighting. Taking the 52300 working face of Daliutai Coal Mine as the engineering background, this study systematically investigates the vertical layered deformation, coordinated roof caving mechanism, and its spatiotemporal lag characteristics by integrating particle flow numerical simulation, attitude-based online monitoring, and multi-source field response verification. From a theoretical perspective, the vertical layered coordinated caving mechanism of the roof under high mining height conditions is clarified, and the spatiotemporal lag characteristics of roof caving are characterized. On this basis, an attitude-based online monitoring system for roof caving is developed, including the design of an attitude sensor and the establishment of a data interpretation algorithm. Numerical simulation results demonstrate that roof caving is not an instantaneous process but undergoes a progressive evolution from immediate roof collapse, main roof bending deformation, crack propagation, to overall structural failure. A key deformation zone is identified at approximately 15–25 m above the coal seam roof, where crack development, interlayer separation, and stress redistribution are most pronounced. By deploying attitude sensors at different vertical levels, real-time measurements of pitch and roll angles are obtained, enabling dynamic characterization of roof bending, rotation, deflection, and fracture processes. Field monitoring results indicate significant stratified responses prior to initial weighting. The lower roof strata exhibit larger amplitude and faster variations in pitch and roll angles, acting as sensitive precursor layers for instability, while the upper thick and hard strata are dominated by slow bending and progressive rotation, controlling the overall failure and concentrated release of ground pressure. Combined with the sudden increase of hydraulic support load and the delayed development of surface cracks, a vertically coordinated caving mode characterized by lower strata initiating failure, upper key strata dominating instability, and delayed surface response is revealed, along with its underlying spatiotemporal lag mechanism. The results show that attitude-based monitoring can capture geometric deformation precursors of the roof prior to significant changes in support load, providing a new technical approach for early identification of initial weighting and precise ground pressure control in high mining height longwall faces.