The cold-start model developed in Part I of this study is verified by comparing its predictions to a variety of experiments in the literature. Using the model, the physical bases for trends observed in various parametric studies are explained. For example, it is shown that near but below 0 degrees C, liquid water flow out of the cathode catalyst layer enables the cell to operate for a significantly longer time than it could if no liquid flow occurred. It is also shown that increasing the current density during start-up reduces the amount of pore space that can be utilized during cold start. On the other hand, decreasing the initial membrane water content or increasing the thickness of the cathode catalyst layer (cCL) increases the capacity of the cell to absorb product water. Finally, during a nonisothermal start the cell potential may remain constant or even decrease, even as the cell heats up. This is due to ice accumulation in the cCL. Once the ice in the cCL melts, allowing liquid-phase drainage, a steep increase in performance is observed. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3592484] All rights reserved.