Comprehensive analysis of hourly extreme precipitation events and timing in Indian urban centres

Abstract

This study presents a comprehensive analysis of extreme hourly precipitation events in Indian urban centres using high-resolution rainfall data spanning 1969–2021. Extreme events were identified using a 99th percentile threshold for each of the 68 urban stations, and GIS tools were employed for geospatial analysis and visualization of spatiotemporal patterns. The findings reveal distinct regional patterns, with higher occurrences of extreme rainfall in the North East and West Coast regions, while certain areas in Central North East and South Peninsular India exhibit exceptions. Seasonal analysis underscores the dominance of extreme events during the summer monsoon, and diurnal patterns indicate that 59% of such events occur from afternoon to late evening. Quantitative results show a significant increase in the frequency of extreme hourly events in over 14% of stations, while 30% of stations experienced a decline. These insights are crucial for understanding the timing, intensity, and trends of extreme rainfall, offering valuable guidance for urban flood management, disaster preparedness, and the development of climate-resilient infrastructure.