Over the past two decades, urban physical processes have been increasingly integrated into numerical weather prediction (NWP) models. However, their performance varies significantly across cities, especially struggling in tropical urban regions due to uncertainties in model initialization and physics. Moving from kilometer-scale to hectometer-scale (100 m) NWP offers many benefits for urban hazard modelling, including the ability to provide information at sub-neighborhood scales and a more accurate representation of convective precipitation. However, this transition also introduces new challenges, primarily due to the partial resolution of atmospheric processes such as turbulence. To fully realize the potential of hectometric models, significant work is still required to improve physics parameterizations and effectively incorporate data at this finer scale.
The Paris 2024 RDP intercomparison of urbanized hectometric NWP models revealed substantial model variability, particularly in simulating Urban Heat Islands (UHIs) and their associated heat plumes. Emerging technologies such as AI, machine learning, digital twins, and new data sources including IoT-enabled sensors, crowdsourced observations, and high-resolution satellite imagery provide opportunities to address these challenges. WP3 focuses on harnessing these advanced modelling techniques and integrating unconventional datasets to enhance forecasting capabilities for urban hazards, while testing their applicability in diverse geographical and data-scarce contexts.