Calculations are made to determine the approximate excess pore vapor density in snow due to a temperature gradient and pore geometry. The approximate excess vapor density is found to be in part produced by the presence of a temperature gradient. This in turn effects the type of crystal wich develops in the snowpack in the presence of a temperature gradient. Comparison with experimental evidence shows excellent agreement. Results presented here indicate that the prediction of crystal habit as determined by temperature and temperature gradient may be possible if the pore geometry can be adequately described.