A method of quantifying a host vehicles collision risk with a foreign object includes the steps of collecting and preserving a short-term history of range and azimuth data on the object and identifying leading edges of the foreign object. The leading edges are linked to previous detected leading edges in the short term history storage data to define a trajectory for the object, and to calculate range and azimuth velocities and accelerations of leading edges of the foreign object based on the leading edge trajectory. A collision risk P is then calculated for the foreign object using the range and azimuth velocities and accelerations according to a predetermined formula. If the collision risk P falls below a pre-set value, the methods of the present invention calculate an evasive maneuver for the host vehicle based on a vector sum of high risk leading edge risks and locations.
