🤖 AI Summary
Existing flash flood early warning systems are predominantly reactive, limiting proactive evacuation and resource prepositioning. This paper proposes a lightweight, parametric proactive warning framework that integrates terrain vulnerability (e.g., water accumulation depth, distance to river channels) with precipitation forecasts to generate interpretable, block-scale threat-level zoning with a 48–72-hour lead time. We introduce the novel Local Threat Severity (LTS) matrix, incorporating 20 terrain-adaptive triggering thresholds that dynamically couple Inherent Hazard Likelihood (IHL) with normalized Hourly Storm Intensity (HSI). The framework leverages GIS spatial analysis, Atlas-14 extreme precipitation normalization, and multi-factor weighted integration. Validation using crowdsourced damage reports from two Texas flood events demonstrates statistically significant spatial agreement (p < 0.01) between LTS outputs and independent damage hotspots, confirming its efficacy in enabling anticipatory emergency decision-making.
📝 Abstract
Flash flood warnings are largely reactive, providing limited advance notice for evacuation planning and resource prepositioning. This study presents and validates an anticipatory, parametric framework that converts landscape vulnerability and precipitation into transparent, zone-aware threat levels at neighborhood scales. We first derive an inherent hazard likelihood (IHL) surface using pluvial flood depth, height above nearest drainage, and distance to streams. Next, we compute a hazard severity index (HSI) by normalizing 24-hour rainfall against local Atlas-14 100-year, 24-hour depths. We then integrate IHL and HSI within a localized threat severity (LTS) matrix using 20 class-specific triggers, requiring lower exceedance in high-risk terrain and higher exceedance in uplands. Applied to two Texas flood events, the LTS exhibits statistically significant spatial association with independent crowdsourced impact proxies, capturing observed disruption hotspots. The framework is computationally lightweight, scalable, and extends actionable situational awareness into a 48-72 hour anticipatory window, supporting pre-event decision-making by emergency managers.