Impact of urban street geometry on outdoor pedestrian thermal comfort during heatwave in Nagpur city

•Microclimate is a significant barrier to walkability in tropical countries.•Urban geometry influences microclimate, and level of influence varies with time.•Low SVF is effective for PTC on E-W streets while high AR for N-S streets.•Urban geometry optimization shall address spatiotemporal variations to improve PTC. Rapid urbanization poses challenges to sustainable transportation, impacting walking as a common mode for accessing transit stations. The Urban Heat Island (UHI) effect, exacerbated by the built environment's heat-absorbing properties, intensifies urban heat stress, hindering outdoor activities and reducing walkability. Urban street geometry impacts thermal comfort through its influences on microclimate. This study aims to investigate the relationship between urban street geometry and pedestrian thermal comfort (PTC), examining how different geometries impact microclimatic conditions and thermal comfort along walking routes in Nagpur city during May 2022. It focuses on four streets with non-uniform urban geometries to investigate their impact on PTC. Field surveys were conducted to collect data at four different hours, from 9:00 a.m. to 6:00 p.m., utilizing MS 6252B Digital Anemometer to measure microclimatic parameters. Using RayMan Pro-software, Sky View Factor (SVF), Mean Radiant Temperature, and modified Physiologically Equivalent Temperature (mPET) were simulated. Correlation analysis revealed that SVF significantly influences PTC, with varying effects throughout the day. Results highlight temporal and spatial variations in microclimate and thermal comfort along street sides. Optimizing street orientation, aspect Ratio, and vegetation improves PTC. The study provides quantitative insights, emphasizing the importance of urban street geometry parameters in enhancing overall PTC.