This study focused on variability of the sea water temperatures observed off the Dangjin Power Plant in the central west coast of Korea for the period of 1998-1999. Spatial averaged temperature shows the annual range of $20.3^{circ}C$, with minimum of $3.3^{circ}C$ in February and maximum of $23.6^{circ}C$ in August. Horizontal distribution patterns are seasonally reversing: The temperatures are increasing toward inshore of the period of April to October, while they are increasing toward of offshore for the rest of year. Spectral analyses of temperature records show significant peaks at M2 and S2 tidal periods, since the water movement in the study area is influenced by strong tide. The responses of temperature variations to tidal phase show different seasonal characteristics: The temperatures are increasing at flood phases in winter and ebb phases in summer. Amplitudes of the components at M2 and S2 periods are $0.8^{circ}C;and;0.5^{circ}C$, accounting for 70-80% of daily variation. Coherency analyses between non-tidal components of temperature and wind speed show that in summer, northerly wind components significantly coherent with temperature at 2.8 days period, while in winter, southerly wind component is coherent with 2.4 days period, with 0.6 and 0.7 day phase-lags, respectively.