The present invention is directed to coated articles demonstrating a transmission of electromagnetic radiation having a frequency of 22 to 81 GHz in the range of 70% to 100%. The articles comprise substrates coated with curable film-forming compositions comprising a first film-forming polymer prepared from at least one hydrophobic monomer, a second film-forming polymer prepared from at least one hydrophobic monomer, and a curing agent. Upon application of the curable film-forming composition to the substrate to form a coating layer, the first film-forming polymer is distributed throughout the coating layer, and the concentration of the second film-forming polymer is greater at the surface of the coating layer than the concentration of the second film-forming polymer within the bulk of the coating layer. The present invention is also drawn to methods of mitigating contaminant build-up on a substrate using the curable film-forming compositions described above.