Precipitation from the Tianshan Mountains is one of the primary sources of water resources in Xinjiang. However, due to a lack of observations, fundamental understanding of cloud and precipitation processes in this area remains limited. This study utilises continuous observational data from two Ka-band millimeter-wave cloud radars located on the northern and southern slopes of the Eastern Tianshan Mountains during the summer of 2024 (June–August) to investigate the statistical characteristics and diurnal variation of summer clouds over the Eastern Tianshan Mountains. Results indicate that cloud coverage in the Eastern Tianshan Mountains during summer is significantly lower than in other regions, with cloud thickness generally less than 5 km and predominantly consisting of single-layer clouds. Cloud frequency on the northern slope (43.36%) is higher than on the southern slope (32.78%), and both cloud top and base heights are higher over the northern slope than over the southern slope. Under the combined influence of solar radiation and topography, cloud and precipitation processes in the Eastern Tianshan Mountains exhibit pronounced diurnal variations—dominated by convective clouds driven by solar heating during the day and by stratiform clouds induced by radiative cooling at night. Differences of land cover and elevation between northern and southern slope, which cause distinct local thermal-dynamical mechanisms, result in vast contrast cloud and precipitation properties in Eastern Tianshan Mountains. This study reveals the statistical characteristics and diurnal variation of summer clouds in the Eastern Tianshan Mountains and preliminarily establishes a physical conceptual model of cloud precipitation formation mechanisms for the first time. These findings provide a reference for future investigations into the macro- and micro-physical characteristics of cloud precipitation processes and offer theoretical support for cloud water resource development in the region. • Remarkable differences of cloud statistics were verified among north and south slopes in ETM. • Land cover and elevation differences are the main drivers for different cloud properties in ETM. • A conceptual model for the development of cloud and precipitation in the ETM has been established.
Zhang et al. (Sun,) studied this question.