The current study investigates how ambient temperature affects streaming potential-induced electrical energy generation triggered by nutrient flow in the stem xylem. During the experiment, the streaming potential of Brassica juncea is measured at various atmospheric temperatures, and the pressure gradient is computed for numerical simulations. It has been found that as atmospheric temperature rises, the increase in transpiration pull augments both axial and radial flow velocities. This enhances the flow loading at the intersection of the stem xylem core region and the porous pitted wall. Consequently, as atmospheric temperature increases, the mechanical stress inside the pitted porous wall also rises. Furthermore, due to convection-driven ionic transport, it becomes apparent that the magnitude of the induced potential at the bottom side of the stem xylem increases with rising atmospheric temperature. Additionally, owing to the ion-partitioning effect caused by differences in electrical permittivity, the concentration of K+ appears to be substantially lower in the pitted porous wall. As atmospheric temperature rises, the streaming electric field strengthens, enhancing both electrical and hydraulic power. Interestingly, atmospheric temperature has almost no influence on energy conversion efficiency. The insights drawn from this study contribute to a better understanding of the impact of atmospheric temperature on the development of green energy generation devices with high power densities.