Urban crash vulnerability during rainfall events: a longitudinal case study from Bexar County, Texas

Abstract

Using radar-based rainfall data and disaggregated crash records, this study provides a high-resolution analysis of the risk of traffic crashes during wet weather in Bexar County, Texas. The goal is to quantify Relative Risk Factors (RRF) of crashes in wet conditions across demographic, temporal, and spatial dimensions. The study overcomes the shortcomings of conventional crash datasets and provides a reproducible framework for evaluating weather-related crash dynamics, building on matched-pair approaches and recent developments in meteorological integration. Results show that precipitation increases crash risk, with strong seasonal peaks in winter and early spring, weekend spikes, especially on Sundays, and increased susceptibility in the early morning and late night. While demographic profiling identifies younger male drivers as a high-risk group under wet conditions, spatial analysis reveals that major thoroughfares, particularly main lanes and ramps, are disproportionately affected. These observations facilitate the implementation of focused interventions, such as youth-oriented educational initiatives, infrastructure improvements (such as improved drainage and skid resistance), seasonal enforcement tactics, and dynamic traffic management systems. The study provides practical advice for policymakers and transportation organizations looking to lower crash frequency and severity during bad weather, and it emphasizes the importance of incorporating meteorological data into traffic safety planning. This work adds to the developing conversation on weather-responsive road safety and infrastructure resilience by promoting a data-informed, context-sensitive approach.