Global warming is an environmental issue keeping all nations alert. Under this consideration, the present work investigates the future thermal sensation of the Greek population. Three periods are selected (2021–2050, 2046–2075, 2071–2100) and two Intergovernmental Panel for Climate Change (IPCC) representative concentration pathway (RCP) 4.5 and 8.5 scenarios. Use of Thom’s discomfort index (TDI) is made, which is calculated from air temperature and relative humidity included in typical meteorological years (TMYs) derived for 1985–2014 and future periods (both IPCC scenarios) for 33 locations in Greece. TDI is discriminated into 6 classes. The analysis shows that there is no significant shift from past to future annual mean TDIs in terms of its classification. The same is found for the summer TDI values. Nevertheless, a distribution of the various TDI classes is provided within the TMYs. Maps of annual TDI values are prepared for Greece by using the kriging method; higher values are found in the southern part of Greece and lower values in the northern. Best-fit regression equations derived show the intra-annual TDI variation in all periods. Also, scatter plots of annual TDIs in the future epochs in comparison with the historical period show a linear relationship.