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Wet snow may cause significant damage to humans and property, and thus, it is necessary to estimate the corresponding liquid fraction (F_L). Consequently, the F_L of wet snow was estimated using a novel technique; specifically, the particle shape irregularity (Ir) was estimated through the particle coordinate information obtained using 2-D video disdrometer (2DVD) measurements. Moreover, the possibility of quantitively estimating F_L via Ir, based on the temperature (T), was examined. Eight snowfall cases from 2014 to 2016 were observed through a 2DVD installed in Jincheon, South Korea, to analyze the dominant properties of physical variables of snowflakes (i.e., the terminal velocity (V_T), particle density (<i>ρ</i>_s), Ir, and F_L) and the corresponding relationships according to the T ranges (−4.5 < T (°C) < 2.5) in which wet snow can occur. It was clarified that the volume-equivalent particle diameter (D)–F_L and D–Ir relationships depended on T, and a relationship existed between Ir and F_L. The analysis results were verified using the Yong-In Testbed (YIT) S-band weather radar and T-matrix scattering simulation. The D–F_L relationship was implemented in the scattering simulation, and the results indicated that the simulated reflectivity (Z_S) was highly correlated with the observed reflectivity (Z_O) under all T classes. These features can provide a basis for radar analysis and quantitative snowfall estimation for wet snow with various F_L values.