In a locomotive having a dynamic braking capability, a method for maintaining an airflow path to a resistive grid disposed within a resistive grid enclosure having an enclosure inlet and an enclosure outlet is provided, wherein the method includes generating an inlet airflow into the enclosure inlet, creating a heated inlet airflow by associating the inlet airflow with the resistive grid such that the inlet airflow absorbs heat generated by the resistive grid, directing the heated inlet airflow toward the enclosure outlet to generate a heated outlet airflow, redirecting at least a portion of the heated outlet airflow to be thermally associated with a structural portion of the enclosure inlet such that the temperature of the structural portion of the enclosure inlet is increased above a predetermined temperature to reduce blockage of the enclosure inlet by snow and recirculating the redirected heated outlet airflow with ambient air being drawn into the resistive grid enclosure.