The purpose of this study is to grasp outdoor heat environment at urban area in Nagano city based on measurement and numerical simulation analysis. Air temperatures and surface temperatures are investigated by the measurement survey. The surface temperature distribution is calculated by numerical simulation analysis. In addition, heat island potential (HIP) and Mean Radiant Temperature (MRT) are calculated, and a detailed factor of the city heat environment is analyzed. Difference of city block density effects to air temperature. Heat Island Potential (HIP) numerical analysis shows 8.6 to 22.5 Celsius degree at day-time.
