Coastal fronts were observed at the research pier HORS at Kashima coast, Ibaraki, Japan, in summer of 2013. Thermistor chain was installed at the tip of the pier and an X-band radar was operated simultaneously. During the observation, coastal fronts approached frequently from the offshore to the pier, inducing abrupt changes in water temperatures, and long crested features which travelled almost steadily to the shore were captured in the radar images. Prevailing components in the spectra of the water temperature and tide level variations, and relationship between the passages of the radar observed fronts and temperature variations suggest that the fronts are internal tides which were propagating to the area.
