Mesoscale climatological studies by Japanese scientists in the recent decade are reviewed. The spatially dense network of the Automated Meteorological Data Acquisition System (AMeDAS) has provided hourly meteorological information since 1976. This review paper focuses on studies, that utilized AMeDAS data on land/sea breeze, extended sea breeze, regional wind distribution, boundary layer climate, local front, and precipitation. In addition to this theme, studies on the winter monsoon are introduced.