On October 16th to 26th, 2013, Japan's eastern coast was affected by three major typhoons. Having monitored the coastal area within the period, abundant data (reflected backscatters in form of consecutive series of grey-scale images) was collected and analyzed. To determine major frequencies and wave-numbers during the storms, one- and two-dimensional Fast Fourier Transform (FFT) are respectively employed for analysis of the original and filtered images. With the main wave-field characteristics in hand and using the linear dispersion relationship, water depths are calculated. Tide-adjusted cross-shore overall profiles are estimated, and analyzed near-shore water depth variation well captures the tidal oscillation within the study period.