Abstract:On the basis of a quality controlled hourly rainfall dataset from 901 automatic weather stations (AWS) in 2013-2019, the fine-scale characteristics of summer rainstorm in Xinjiang are analyzed. The results show that the rainstorm days in northern Xinjiang are more than in southern Xinjiang, and the rainstorm days in mountain areas are more than in plains. In addition to the middle section of the Tianshan Mountains, parts of the northern slope of Kunlun Mountains in the southeastern part of southern Xinjiang also have rains frequently. In July (August), rainstorm days in Xinjiang are the most (fewest), and the proportion of short-time severe precipitation is the highest (lowest). In July, local convective rainstorm is the major event while in August regional systematic rainstorm is dominant. In Xinjiang, 75.3% of the stations had short-time severe precipitation during the heavy rain periods. The short-time severe precipitation events occurred frequently in the regions where the annual average number of heavy rain days was less than one day, but the regions with more heavy rain days were not hit by short-time severe precipitation very often. The proportion of short-time severe precipitation events in heavy rainfall periods in Xinjiang increases with the decrease of altitude, exceeding 85% stations below 500 m. The “daytime rain” characteristics of heavy rain in Bortala, Karamay, northern Tacheng and western Altay of northern Xinjiang are noticeable. The average rainfall time of the above-mentioned regional rainstorm days is short, and the occurrence percentage of short-time heavy rainfall events is high. The peaks of the regional average accumulated precipitation, frequency and average intensity of convective rainstorm often appear from afternoon to early evening. The average rainfall hours of rainstorm days in the Ili River Valley and the northern slope of Tianshan are more, but the short-time severe precipitation is at a low proportion. The peaks of accumulated precipitation and frequency often occur from night to morning, while the peak value of the average precipitation intensity appears from evening to the first half of the night, dominated by the systematic rainstorm. The diurnal variation of rainstorm in southern Xinjiang is more complicated than that in northern Xinjiang.