| Summary: | We investigated the distribution of air temperature (T<sub>a</sub>) and the factors affecting it in low-rise areas surrounding an isolated high-rise building during the Japanese winter. The study site was the central part of a regional city in Japan (36°5′ N, 140°12′ E), lying north-east of the Tokyo metropolitan area. The daytime surface temperature (T<sub>s</sub>) in the shade is generally considered to be comparable to T<sub>a</sub>; however, according to airborne remote sensing conducted in December 2009 where a multi-spectral scanner was installed on a fixed-wing aircraft, T<sub>s</sub> for pavements in the shade of a high-rise building was significantly lower than T<sub>a</sub> of sub-urban areas, indicating an influence of cold storage on T<sub>s</sub>. Then, we conducted mobile observations using instruments (thermocouple, four component radiometer, and so on) installed on a bicycle in January 2016 to investigate the detailed distribution of T<sub>a</sub> and the factors affecting it. The results showed the T<sub>a</sub> over the pavements in the shade of the high-rise building was lower than the T<sub>a</sub> of sunlit areas in the same urban area by −2 °C and lower than the T<sub>a</sub> of sub-urban areas by −1−1.5 °C, although the advection effect was large due to strong winds around the building. In conclusion, a locally lower T<sub>a</sub> compared to the surrounding areas can develop during the day in winter, even in spaces that are open to areas beyond the canopy.
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