Flashing light module for a traffic safety cone has multiple stacked arrays of LED lights providing 360-degree visibility around the cone. The LED arrays are mounted onto a battery container, and a transparent or translucent housing covers the arrays and mounts onto the battery container to provide a water-tight seal for the enclosed electronics. The battery container fits into the upper opening in a truncated traffic safety cone. The LED light arrays have a variable flash rate. Optionally, an ambient light sensor is used to control the intensity of the light produced by the LED lights.