The invention discloses a short-time early warning system for severe convection weather, and the system comprises a business management module which achieves duty shifting registration, system log, forecast grading, and business flow; a data preprocessing module which achieves real-time data collection, data quality control, data preprocessing, and severe convection weather diagnosis; a short-time temporary forecast early warning module which achieves a weather background and case library, severe convection monitoring analysis, severe convection potentiality forecast, severe convection short-time temporary forecast, and the manufacturing of forecast early warning products; and a product distribution module which achieves product packaging, early warning information inter-cut, short-message/audio-signal services, and fax/E-mail. The system constructs base information, and carries out the statistics of severe convection generation factors of the Tibet region in recent years. The system achieves the research of the large-scale conditions of severe convection weather in the Tibet region, and divides different circulation patterns for different regions. The system employs a method of composite analysis to synthesize the characteristics of an environment field, builds an early-warning model, and has higher forecast accuracy and long forecast time efficiency for the severe convection weather in the Tibet region.