  I examine a variety of snow crystal growth measurements taken at a
temperature of -5 C, as a function of supersaturation, background gas pressure,
and crystal morphology. Both plate-like and columnar prismatic forms are
observed under different conditions at this temperature, along with a diverse
collection of complex dendritic structures. The observations can all be
reasonably understood using a single comprehensive physical model for the basal
and prism attachment kinetics, together with particle diffusion of water vapor
through the surrounding medium and other well-understood physical processes. A
critical model feature is structure-dependent attachment kinetics (SDAK), for
which the molecular attachment kinetics on a faceted surface depend strongly on
the nearby mesoscopic structure of the crystal.
