1. A method, comprising: selecting, by a computing device of a vehicle, a portion of a three-dimensional (3D) point cloud representing an area at a height greater than a threshold height from a surface of a road of travel of the vehicle; identifying a shape in the selected portion; determining, using the computing device, that the identified shape represents a construction zone sign based at least on an outline of the shape; determining a type of the construction zone sign based at least on the identified shape; determining a severity of road changes based on the type of the construction zone sign; and controlling, using the computing device, the vehicle based on the type of the construction zone sign and the severity of road changes.