This study seeks to assess the bioclimatic conditions of some selected stations in Nigeria from 1981 to 2010 using meteorological data input from the Nigerian Meteorological Agency (NIMET). The specific objectives were to analyze the spatiotemporal variability of the key weather parameters critical to bioclimatic conditions, evaluate the monthly and seasonal variation of the bioclimatic conditions and analyze the spatiotemporal variation of the human bioclimatic conditions over the area. The study applied the use of two bioclimatic indices, namely physiological equivalent temperature (PET) and Universal Thermal Climate Index (UTCI). PET was computed using the RayMan model, while UTCI was computed using the Bioklima model. The bioclimatic conditions were observed to vary seasonally as thermal stress levels particularly increased in the months of March to May and these months correspond to the pre-wet period of the year. The conditions, however, improved during the wet and dry periods. The early hours of the day (0600 Local Standard Time) were characterized mostly by no thermal stress conditions; however, the northern regions were cooler than the other parts of the country. The frequency of thermal stress categories for each station also revealed the threshold of the thermal stress condition over each station. The result from this study provides useful bioclimatic information applicable in the development of adaptive strategies and efficient planning with respect to the thermal environment.