Urbanization and global warming have significantly affected the quality of urban life, particularly thermal comfort in outdoor spaces. Thermal comfort is a key determinant of public health, social cohesion, and urban livability. In Tabriz, one of Iran’s largest metropolises with a cold-moderate climate, rapid urban expansion, high building density, reduced vegetation, and inappropriate street orientation have intensified urban heat islands (UHI) and degraded outdoor comfort. This study aims to identify key drivers of thermal comfort and develop future scenarios for sustainable urban planning.A mixed-method approach was employed, combining quantitative and qualitative techniques. Data were collected through literature review, expert consultation (Delphi method), and structural analysis using MICMAC software. Thirty experts in urban planning, climatology, and environmental studies participated in the Delphi and scenario-building processes. Results revealed five critical drivers: urban heat islands, height-to-width ratio of streets, wind speed and direction, street orientation relative to prevailing winds, and vegetation cover. ScenarioWizard was applied to generate 15 plausible scenarios, ranging from desirable to critical futures. Findings indicate that increasing vegetation, reducing UHI, and designing streets aligned with wind flow significantly improve thermal comfort. Conversely, high building density and reduced greenery exacerbate discomfort.The study concludes that integrating climate-responsive design, scenario-based planning, and urban ecology perspectives provides a robust framework for enhancing thermal comfort in Tabriz. Policy recommendations include revising current urban management strategies, promoting green infrastructure, and adopting adaptive design guidelines.