Abstract: Based on the disastrous forecast of grey system theory, the disastrous forecast model for winter strong low temperature and frost was established, combined with the historical temperature date in the Menghai County, Yunna Province. The years in which the minimum temperature under -1.4and frost emerged, and the disastrous years in the future would emerge, were predicted. The predicted results were accorded with the observation data by model validating. The corresponding countermeasures of disaster reduction were put forward.

Key words: Gray system theory, Gray system theory, Strong lower temperature and frost, Disastrous years, Forecast model