A Supplemental Note to the Combined Role of Kinematics, Thermodynamics and Cloud Physics Associated with Heavy Snowfall Episodes

A miniclimatological study of upper air thermal conditions occurring in the ascending air of synoptic circulations that yielded heavy snowfall amounts strongly supports the premise of Auer and White (1982). These investigators claimed that regions of maximum rate of condensate that occurs near the level of nondivergence at temperature regimes near -15 degrees C must be suspected of producing heavy snowfall episodes. That is, heavy snowfalls are expected to occur in regions where the level of nondivergence (maximum vertical velocities for saturated ascent) is coincident in elevation with the maximum growth rate of dendritic ice crystals. This study corroborates that for heavy snowfall, saturated ascent through the level of nondivergence must be confined to the envelope of 304-309 K (i.e., a 600-mb temperature between -13 and -17 degrees C).