Extreme Short-Term Heavy Precipitation Hazard Zoning Study in Linyi City

Based on the hour-by-hour precipitation data from national and regional-level surface meteorological automatic stations in Linyi from 2011 to 2020, the statistics of short-term heavy precipitation show the following characteristics:(1) Short-term heavy precipitation in Linyi shows obvious interannual and inter-monthly variations, and its frequency is on the rise after 2015, with the extreme short-term heavy precipitation showing high frequency and high intensity. (2) During the June-September flood season, July is the month with the highest frequency of short-term heavy precipitation, followed by August, with the ratio of short-term heavy precipitation to heavy rainfall reaching 82.2% in August. (3) There is a clear pattern of daily changes in short-term heavy precipitation, with the high incidence concentrated in the late afternoon to evening and early morning. (4) The high-frequency areas of short-term heavy precipitation in Linyi include Hedong District, south-central Yinan County, southern Mengyin County, northwestern Jounan County, southeastern Yishui County, northern Tancheng County, and southeastern Linshu County in Linyi City.