Contemporary tensile membrane roofs (TMRs) have been gaining an increased popularity in projects featuring large spans over the past decades. Such doubly-curved roof forms demonstrated significant potentials due to their ability to mitigate undesirable external influences and enhance indoor environmental quality, especially in cooling-dominant climates of the Mediterranean and North African regions. However, their solar-thermal behaviors are profoundly different from conventional buildings, and the current understanding of their performance is limited, posing a challenge in harnessing the full capabilities of such innovative roof forms in architectural practice. This research seeks to parametrically study the unconventional solar-thermal properties of TMRs of varying orientations and geometrical configurations within the hot-desert climate of Aswan (23.97 degrees N), Egypt. The methodological procedure is realized through 4 phases. The first entails developing a parametric algorithm under the computational environment of Grasshopper 3D to derive the modeling of TMRs via numerical transformations of geometrical and structural variables. A total of 21,600 TMR models were generated by manipulating various input parameters. These models were subjected to solar simulations and heat transfer analysis using Ladybug plugin, in combination with a specially developed Python code. The investigations involved staggering 482,892,032 computational runs in the second phase. In the third phase, a set of 25 internal (geometry-related) and external (weather-related) independent variables were carefully defined, which represent key factors influencing the performance of TMRs. They provide a comprehensive understanding of the complex interactions with the resulting 5 dependent variables in the last phase, accounting for shortwave, longwave and convective heat transfers, surface temperatures, in addition to the overall performance index. The outcomes of this work shall provide architects and practitioners with essential data on the performance of TMRs in harsh hot-desert contexts.