In fractal, porous, and cranny rough media, the diffusion of the electromagnetic (EM) field differs from that in piecewise smooth media. This phenomenon is known as an anomalous diffusion. To study the influence of anomalous diffusion on EM signals, we use the fractional time derivative and derive a governing equation describing the subdiffusion process of electric fields in rough media. Three-dimensional (3D) forward modeling of the time-domain airborne EM (AEM) is performed using the finite-difference method and frequencytime transformation. We verify the accuracy of our forward modeling method by comparing it with semi-analytical solutions for a layered earth model. The numerical results show that as the conductivity of rough media decreases with time, the amplitude of the EM field decreases during the early periods but increases during later periods compared to non-rough media. The EM field does not diffuse in the classical mode of the "smoke ring, but instead demonstrates a "trailing pattern, meaning that it maintains its maximum value at positions close to the source and diffuses outward and attenuates until it vanishes.