Abstract: A warning light is provided to be coupled to a stop sign. The warning light includes a main unit, a holder for cooperating with the main unit to couple to the stop sign, a solar cell for converting solar energy into electrical energy, a light emitting element disposed in the main unit, an energy storage device coupled to the solar cell for storing the electrical energy, and a charge control circuit coupled to the solar cell, energy storage device and light emitting element. The charge control circuit selectively directs electrical energy from the solar cell to energy storage device, or from the energy storage device to the light emitting element.