The southeastern Tibetan Plateau (TP) is the critical region of water vapor transport over the TP. Ground-based Ka-band cloud radar (KaCR) measurements collected at the Motuo National Climate Observatory in 2019 were used to analyze the physical properties of clouds at the front of the water vapor channel over the TP. The cloud top heights (CTHs) measured by the KaCR were verified through a comparison with observations from the Fengyun-4A (FY-4A) satellite at the same location. The KaCR-obtained CTHs were generally consistent with the FY-4A-obtained CTHs, although the KaCR slightly overestimated the CTHs of nonprecipitation clouds and underestimated the CTHs of precipitation clouds. Negative deviations between the KaCR- and FY-4A-obtained CTHs increased with rainfall rate. Cloud cover frequently occurred over Motuo, with an annual mean occurrence frequency of 65.3%. Clouds tended to form frequently at night and dissipate gradually in the daytime. Two peaks in the cloud base height (CBH) distribution were observed in Motuo, located at 0–1 km and 2–3 km, corresponding to precipitation and nonprecipitation clouds, respectively. The CTHs reached a peak at 6–7 km, which might be related to precipitation clouds. Moreover, a maximum CTH probability was observed in the midnight-early morning hours during the rainy season, while the CTH frequency peaked in the evening during the dry season. In addition, low and middle clouds were prevalent in Motuo for the period of observation in 2019. Understanding the characteristics of clouds over the TP will provide key validations of satellite measurements and promote research on cloud forces over the TP.

青藏高原东南部（TP）是整个TP上水汽输送的关键区域。2019年在莫托国家气候观测站收集的地面Ka波段云雷达（KaCR）测量用于分析TP上水蒸气通道前部云的物理特性。通过与来自同一位置的风云4A（FY-4A）卫星的观测结果进行比较，验证了由KaCR测量的云顶高度（CTH）。尽管KaCR稍微高估了非降水云的CTH并低估了降水云的CTH，但KaCR获得的CTH通常与FY-4A获得的CTH一致。KaCR和FY-4A获得的CTH之间的负偏差随降雨率的增加而增加。莫托上空经常发生云层覆盖，年平均发生率为65.3％。夜间往往会形成云，而白天则逐渐消散。在墨tu观测到云底高（CBH）分布的两个峰值，分别位于0-1 km和2-3 km，分别对应于降水云和非降水云。CTHs在6-7 km达到峰值，这可能与降水云有关。此外，在雨季的午夜至清晨，观察到最大的CTH概率，而在旱季的晚上，CTH频率达到峰值。此外，在2019年的观测期中，低层云和中层云在Motuo普遍存在。了解TP上的云的特征将提供卫星测量的关键验证，并促进对TP上云力的研究。夜间往往会形成云，而白天则逐渐消散。在墨tu观测到云底高（CBH）分布的两个峰值，分别位于0-1 km和2-3 km，分别对应于降水云和非降水云。CTHs在6-7 km达到峰值，这可能与降水云有关。此外，在雨季的午夜至清晨，观察到最大的CTH概率，而在旱季的晚上，CTH频率达到峰值。此外，在2019年的观测期中，低层云和中层云在Motuo普遍存在。了解TP上的云的特征将提供卫星测量的关键验证，并促进对TP上云力的研究。夜间往往会形成云，而白天则逐渐消散。在墨tu观测到云底高（CBH）分布的两个峰值，分别位于0-1 km和2-3 km，分别对应于降水云和非降水云。CTHs在6-7 km达到峰值，这可能与降水云有关。此外，在雨季的午夜至清晨，观察到最大的CTH概率，而在旱季的晚上，CTH频率达到峰值。此外，在2019年的观测期中，低层云和中层云在Motuo普遍存在。了解TP上的云的特征将提供卫星测量的关键验证，并促进对TP上云力的研究。