The northeastern slope of the Tibetan Plateau, situated in a complex terrain and the monsoon-westerly transition zone, experiences frequent convective storms and high disaster risk. Based on CINRAD radar and ERA5 reanalysis data from 2015 to 2019, a high-resolution convective climatology was established, and its environmental fields were diagnosed. Results indicate a significant topographic anchoring effect on convection, with persistent hotspots located in the Yellow River valley-Xinglong Mountain, the eastern Qilian Mountains, and the sharp-bend reach of the Yellow River. Moderate convection dominates (64.7 %), while deep convection has a low frequency but high local intensity. The most active month seasonally is July, with June and August exhibiting similar levels of activity. The convective activity in July is most active during the season, with levels in June and August being similar. The configuration of synoptic patterns indicates a synergistic mode of “upper-level trough, lower-level convergence, and strong moisture transport” for convective days. Diurnal variation is characterized by a peak in the afternoon (13:00–18:00 BJT) and is weakest in the early morning to morning, consistent with the synergistic trigger between solar radiation and terrain convergence. Atmospheric environment diagnostics reveal that, compared to non-convective events, convective events have higher CAPE, stronger updrafts, greater vertical wind shear, and more abundant water vapor in the two hours prior to triggering. The statistical distribution of storm scales exhibits an exponential decay with a “long-tail” pattern, with approximately 80 %–85 % of convective events having a propagation distance of less than 20 km and a max area of less than 200 km². The propagation direction of convective activity exhibits inter-monthly shifts, trending eastward/southward in June, shifting northward to east-southeastward in July, and westward/northward in August. These findings reveal the mechanisms by which large-scale circulation and local topography jointly influence convection, providing critical scientific support for monitoring and early warning systems for severe convection in the Tibetan Plateau and its surrounding areas, as well as for disaster risk prevention and control.
CORE (COnnecting REpositories)
CORE (COnnecting REpositories)