The sensitivity of moist convection to a number of low-level thermodynamic parameters is examined with a high-resolution, nonhydrostatic numerical model. The parameters examined are the surface temperature dropoff (defined as the difference between the potential temperature measured at the surface and that in the well-mixed boundary layer), the surface moisture dropoff (defined similarly for moisture), the boundary layer moisture dropoff (defined as the vertical decrease in moisture within the boundary layer), and the depth of the moisture. The typical variability in these parameters is estimated from two field experiments in northeastern Colorado. Sensitivity is then defined relative to this typical observational variability. Two convection initiation cases from northeastern Colorado are examined. In both cases, convection initiation is found to be most sensitive to the surface temperature dropoff and the surface moisture dropoff. It is found that variations in boundary layer temperature and moi... Abstract The sensitivity of moist convection to a number of low-level thermodynamic parameters is examined with a high-resolution, nonhydrostatic numerical model. The parameters examined are the surface temperature dropoff (defined as the difference between the potential temperature measured at the surface and that in the well-mixed boundary layer), the surface moisture dropoff (defined similarly for moisture), the boundary layer moisture dropoff (defined as the vertical decrease in moisture within the boundary layer), and the depth of the moisture. The typical variability in these parameters is estimated from two field experiments in northeastern Colorado. Sensitivity is then defined relative to this typical observational variability. Two convection initiation cases from northeastern Colorado are examined. In both cases, convection initiation is found to be most sensitive to the surface temperature dropoff and the surface moisture dropoff. It is found that variations in boundary layer temperature and moi...