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In order to ensure the security of expressway driving in snow weather, by using the expressway traffic accident data of 2000 to 2012 over Hebei Province which from the Hebei Province Expressway Traffic Police Corps, the spatial and temporal distributions of traffic accidents in snow weather are analyzed statistically. The results show that: (1) The changes of the monthly distribution were significant, and the high incidences of traffic accidents in snow weather occurred in January, February, November and December, which account for 87.2% of the traffic accidents in snow weather in all the year. (2) There was uneven spatial distribution. The highfrequency accident spots of expressway in snow weather appeared in Expressway G4, G6, S010, etc., in Zhangjiakou region, in which the traffic accidents account for 51.1% of the total traffic accidents in snow weather. Based on the factors such as meteorological, road surface, terrain, etc., using the expert judgment method, through analyzing 29 traffic accident cases in snow weather from 2008 to 2012, the early warning indicators and the classification standards for expressway traffic in ice and snow weather in Hebei Province are proposed, and the warning accuracy rate of grade index reaches 73.9%,84.2% in G2 and G6, respectively．The indexes provide references for meteorological services and disaster prevention and mitigation.