a detectable warning system , for tactily signaling the presence of a terrain transition to a pedestrian , using a plurality of detectable warning domes that are arranged in a grid within a detectable warning carrier assembly . the detectable warning carrier assembly comprises a carrier layer being one of a top layer and a base layer of thermoplastic material with heat resistant detectable warning domes therebetween . the carrier layer is heated and adhered to a pavement surface . the detectable warning domes protrude from the pavement surface in an evenly spaced pattern that is detectable by the pedestrian using a cane or other guidance instrument .