Accurately estimating the operating temperature of solar photovoltaic modules is crucial for realistic PV system output calculations. This study introduces a computationally efficient one-dimensional transient Finite Difference Method model, developed from first principles, to evaluate the temperature distribution within a PV module throughout the day and predict the operating cell temperature. The model incorporates environmental factors such as plane-of-array irradiance, wind speed, wind direction, ambient air temperature, and the sun’s position relative to the PV modules. It is applicable to both ground-mounted fixed-tilt and single-axis tracking configurations, addressing a gap in thermal modelling for tracking PV systems, which are often limited to software packages or neural network models. Model validation against experimental data confirms its accuracy in predicting module temperatures for both configurations.