In 2019, the average summer precipitation in Shandong was 414.6 mm, which is 3.0% more than that in normal years. The number of precipitation processes is less, the spatial and temporal distribution of precipitation is uneven, and the more precipitation is mainly caused by Typhoon LEKIMA. If the typhoon precipitation is removed, the summer precipitation in Shandong would be 41.8% less than that in normal years. In summer, the western Pacific subtropical high continued to be strong and lay westward and southward, accompanied with the circulation pattern of “two troughs and one ridge” in the mid-high latitude of Eurasia, which is the direct reason for the obviously less summer precipitation in Shandong as the impact of typhoon is removed. The El Niño events from September 2018 to June 2019 and the persistent high sea surface temperature in the tropical Indian Ocean play an important role for the strong, westward, and southward western Pacific subtropical high. The persistent positive phase of the North Atlantic sea surface temperature tripole is closely related to the stronger ridge over Lake Baikal.