The climatic characteristics and temperature profiles of freezing rain in China are analyzed based on the observational data at 650 stations in China from 2000 to 2015. The freezing rain of China is generally in stripe-shape spatial distribution. The stations with freezing rain over 100 station-hours are mainly concentrated at the southeast areas of Southwest China and high-elevation mountainous areas of Eastern China. There are mainly two types of freezing rain temperature profiles, including single-warmlayer profile and double-warm-layer profile. The freezing rain profiles of mountainous area and urban area in Southwest China are similar to each other, and the freezing rain in Central and East China shares the similar single-warm-layer profile. The profiles in South China show the characteristics of freezing rain's profile in both Southwest China and Central/East China as the position of stations. PA of freezing rain's profiles is negatively correlated with NA, with correlation coefficients ranging from −0.36 to −0.70. The configuration of weak cold/warm layer (both smaller than 150 ∘ C⋅hPa) is one of major reasons causing frequent freezing rain at mountainous areas of Southwest China. The more obvious the change of NA with the variations of PA is, the more the freezing rain is likely to occur.

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Based on 30 complete wire icing processes lasted longer than 24 h observed from the Enshi, Jinsha, Dacaoping and Shennongding of Shennongjia in mountainous areas of Hubei province during the winter of 2008–2016, the macroscopic effects of rain–fog weather on the ice accretion process were analyzed. Furthermore, the distribution characteristics of key simulation parameters in supercooled fog (SF) and freezing rain (FR) were discussed according to the physical model of icing process. Finally, the evolution characteristics of the simulated ice thickness in rain–fog weather were proposed. Results showed that the duration of ice accretion in mountainous areas is the key factor affecting the maximum ice thickness; the freezing rain is most frequent during the glaze icing process, which leads to the substantial growth of ice thickness. The average growth rates of ice thickness with and without freezing rain are 1.26 mm h−1 and -0.11 mm h−1, respectively. Collision rate is the main parameter for inhibiting ice accretion of SF, with an average value of ∼ 0.1, while freezing rate is the main parameter for inhibiting ice accretion of FR, with an average value of ∼ 0.6. The ice accretion of SF shows the characteristics of periodic growth, while the ice accretion of FR shows the explosive growth of ice thickness, which makes the simulated values of icing closer to the observations. The ice formation efficiency of FR was more than twice that of SF, with a negative feedback mechanism to the ice accumulation of SF.