Due to cold waves, some regions of the southern China experience low or even extremely low temperatures in winter. When the temperature drops sharply, it may cause severe low temperatures, rain/snow and freezing disasters. These disasters seriously affect transportation, power safety, and other social production activities. This study used the precipitation and average temperature data from 258 stations in 12 provinces of the southern China between 1951 to 2020 to extract the low temperature events and screen the characteristic indexes, which were negative accumulated temperature, accumulated precipitation and daily maximum precipitation. The index values of different return periods (RP=5, 10, 30, 50 a) were calculated to assess the hazard of low-temperature rain, snow, and freezing events accordingly. Combined with the distribution of highway and railway networks, the exposure of traffic lines was analyzed. The results showed that the areas with more events were concentrated in Guizhou, Hubei, Anhui, and Jiangsu. The duration was in a zonal distribution, and the boundaries of high-value areas were clear. Among them, the longer duration areas were in Guizhou and Hunan. The maximum value of negative accumulated temperature was -78.2℃, the maximum value of accumulated precipitation was 83.2 mm, and the maximum value of daily precipitation was 38.9 mm (RP=50 a). Hubei, Hunan, Guizhou, Anhui and Jiangxi were high risk areas, and the above-mentioned areas all had road sections with high risk.
