Characteristics of Short-term Heavy Rainfall at Different Intensity Levels in Foshan City over the Past 10 Years

CHENG Yinlin; HE Qiurui; MAI Lingling; CHEN Chen

doi:10.3969/j.issn.1007-6190.2025.04.006

Abstract：To enhance the understanding of the occurrence patterns of short-term heavy rainfall in Fos-han City and improve the forecasting and warning capabilities for such rainfall and its derived disasters,hourly observational data from 194 automatic weather stations in Foshan from 2015 to 2024 were analyzed to investigate the variation characteristics of short-term heavy rainfall at different intensity levels and time peri-ods.The results indicate the following.(1)The annual trends in the frequency of short-term heavy rainfall vary inconsistently across different intensity levels,with greater interannual fluctuations as intensity increa-ses.Heavy rainfall primarily occurs between 13:00-20:00 from April to September.(2)Its frequency is generally higher between 14:00-20:00 than at other times,with the smallest interannual fluctuations during this period.The frequency shows an increasing trend from 02:00-08:00 and 14:00-20:00 but a decrea-sing trend from 20:00-02:00 and 08:00-14:00.(3)The spatial distribution of short-term heavy rainfall frequency varies significantly across different intensity levels and time periods,with an inverse relationship between frequency distribution and the coefficient of variation.(4)In operational forecasting,particular at-tention should be paid to short-term heavy rainfall occurring between 14:00-20:00 during the rainy season in the eastern part of Nanhai District and the southern part of Shunde District.This study provides critical in-sights into the spatiotemporal patterns of short-term heavy rainfall,offering a scientific basis for improved dis-aster prevention and urban resilience in Foshan City and similar subtropical regions.