This short communication proposes a new scaling law, on the basis of which scale-model experiments on a large-scale wind-aided fire phenomenon can be designed. The proposed scaling law takes into account the Froude number, which is defined using the flame height. The results of two different scale-model experiments on the fire whirls observed after the Great Kanto Earthquake are reported. The wind velocities in the scale-model experiments are determined using the proposed scaling law. The scale-model experiments successfully reproduce fire whirls similar to those observed after the Earthquake, thus validating the proposed scaling law.