Abstract:Based on the hourly precipitation data in Shandong Province during 1961-2012 from 74 weather stations, spatio temporal distribution characteristics of short duration and long duration precipitation events in flood season (May-September) in Shandong are analyzed. The results show that: (1) the increase of process precipitation and process duration makes the total precipitation amount in Shandong in flood season increase slightly. The frequency of continuous precipitation processes, the increase of process precipitation, and the increase of process duration make the greatest contribution to the increase of total precipitation. (2) The total precipitation of short duration is the most in the mountain areas of the central and southeast parts of Shandong while the persistent total precipitation is the most in the southeast coast of Shandong and the eastern part of the peninsula. The short duration precipitation and the average rainfall intensity are the largest from southeast Shandong to Dezhou region, and, in contrast, the sustained rainfall and the average rainfall intensity are the largest in the eastern part of the peninsula and the southeast part of Shandong. (3) The short duration rain intensity peak is greater in the surrounding areas of the mountain area in central Shandong, and the sustained rain intensity peak is higher in the southern and southeastern parts of Shandong as well as the eastern part of the peninsula. (4) The short duration precipitation in the mountain area of central and southern parts of Shandong and some places of the peninsula generally occur from 13:00 BT to 18:00 BT in the afternoon. Around the mountain area in central Shandong and the coastal area of the peninsula, it rains mostly at night and also the beginning time of the continuous precipitation appears at night mostly.