Traffic jam warning method

The invention belongs to the technical field of intelligent transportation facilities, and particularly relates to a traffic jam warning method, which is characterized in that a control unit is used for receiving, processing or sending information; a data processing unit is used for receiving and processing data information detected by an RFID (Radio Frequency Identification Devices) reader; a storage unit is used for storing the data information in the processing unit; a traffic flow average speed detecting unit is used for judging a range in which traffic flow weighted mean velocity falls, and sending an instruction to a display unit and a voice unit according to a converted signal; the display unit and the voice unit are used for warning a traffic jam situation and providing an optimum running route. A main body structure of a traffic jam warning device comprises the control unit, the data processing unit, the storage unit, the traffic flow average speed detecting unit, a signal converting unit, the display unit, the voice unit, an RFID electronic tag, an RFID base station, the RFID reader, a multi-functional displayer and an LED (Light-emitting Diode) indicator light. The traffic jam warning device is simple in structure design, convenient to use, low in cost, convenient to apply and popularize, and friendly in application environment.