Abstract: With the daily precipitation data of Tazhong Station in the hinterland of Taklimakan Desert from 1997 to 2017, the daily variation of precipitation and extremely strong precipitation were analyzed. The results showed that with increasing trend of annual precipitation, the rainy day number was reducing. Especially both the days and volumes of big rainy had obviously increased. The evolvement of rain had enhanced. The rainy days more happened in June, the strongest hourly rain was 8.4 mm which accrued at the end of spring on May 14th. The diurnal variation of precipitation presented many peaks and troughs. The maximum precipitation appeared near midnight at 23:00 (Beijing Time). The maximum precipitation frequency occurred at 06:00 (Beijing Time). The precipitation intensity and frequency played different parts in rain. From afternoon to eve it presented strong precipitation intensity with low precipitation frequency. However, from midnight to day it presented weak precipitation intensity with high precipitation frequency. Short-duration precipitation within 1-3 hours were dominated events in the hinterland of Taklimakan Desert and the contribution rate of short-duration precipitation events within 1-3 hours to total precipitation were up to 61.76%.The threshold of the 99th percentile for daily rainfall and hourly rainfall were 15.3 mm·d^-1 and 6.0 mm·h^-1, respectively. Actually, contribution rate of extreme strong rainfall higher more than the threshold of the 90th percentile was close to half of total precipitation. The extreme strong rainfall events occurred mainly under the 500 hPa circulation background of the south branch through, trough-line and thin cyclonic wind fields which lied at the south of 40°N in the Southern Xinjiang Basin. And the humidity was close or excess to 10 g·kg^-1 at 850 hPa in the Minfeng which was at the southwest of Taklimakan Desert. The continuous character of precipitation was worse, and there were more short term precipitation at mesoscale and micro scale in local.

Key words: hinterland of Taklimakan Desert, diurnal variation of precipitation, threshold of extreme strong rainfall, weather background