The initiation of springtime mesoscale convective systems (MCSs) over the U.S. Great Plains is strongly supported by synoptically forced uplift. In this study, we first quantify these uplift mechanisms by numerically solving the quasi-geostrophic omega equation in Q-vector form. To provide a process-based assessment, Q vectors are decomposed into shearwise and transverse components, representing changes in the direction and magnitude of the potential temperature gradient along the geostrophic motion. The composite analysis reproduces the upper- and lower-tropospheric synoptic conditions favorable for MCS initiation, which have been well documented in the literature. We reveal that shearwise ascent, induced by a baroclinically organized trough–ridge couplet, is the leading contributor to total dynamical ascent. The contribution of an upper-level jet, which induces upward motion in its right entrance region through geostrophic frontogenesis by confluent motion, is minor as indicated by weaker transverse ascent. Likewise, the lower-tropospheric transverse ascent, induced by warm frontogenesis at the exit of the Great Plains low-level jet, plays a secondary role compared to shearwise ascent. Furthermore, MCSs initiated under stronger shearwise ascent tend to grow into larger, more precipitating storms, while no significant sensitivity to initial transverse ascent is observed throughout the MCS lifecycle. This study underscores the critical role of baroclinic wave amplification not only in the genesis but also in the subsequent evolution of MCSs, offering operational insights for their prediction.