In this work, the relationships of pedunculate and Turkey oak tree-ring width and stable carbon isotope ratio (δ13C) with climatic variables (temperature and precipitation) through 50-year chronology were analyzed. Tree sensitivity over time was assessed in terms of Pearson’s correlation strength and the moving correlation with a 20-year window (presented in the form of heat maps) was calculated for the 1960−2010 timespan. The obtained results indicate that ongoing intensive climate changes induce variations in the correlation strength between climatic variables and the tested tree-ring parameters. Moreover, compared to tree-ring width, stable carbon isotope records were found to be more sensitive to, and to vary more strongly with, climate variations. The strongest correlations were obtained between temperature and precipitation during the late spring months and isotope content. Likewise, climatic conditions in the preceding year strongly correlated with tree-ring width, while isotope ratio was more sensitive to the climate in the current year. Although species-specific differences in correlation strength were noted, their variations were rather weak and did not follow a discernible pattern.