This paper presents a two-directional Stefan's solution for computing the freeze and thaw of soil columns. Use of an inverted set of equations to drive the soil freeze-thaw from the bottom is a significant improvement to the original freeze-thaw model. Simulations using the algorithm compared well with the 0¿C isotherm interpolated from observed data at Arctic, Subarctic and cool temperate sites with different frost conditions that range from permafrost to seasonal frost across a north-south gradient in North America. The incorporation of explicit freeze-thaw parameterization in hydrologic and land surface models would enable realistic simulation of soil temperature, soil moisture and runoff/infiltration and hence energy, water and greenhouse gas exchange processes in high latitudes.