Explicit Microphysics and Diabatic Initialization

The presentations I gave at the NetFAM Workshop on Clouds and Precipitation are based on my work, and that of my colleagues, on the Local Analysis and Prediction System (Albers et al. 1996). Equations and graphics from the powerpoint presentation that accompanies this article will not be replicated here; the reader may find additional clarity by referring occasionally to the presentation material. LAPS is a software package that ingests meteorological observations, creates hourly three-dimensional grids of state variables and clouds, and produces initialization grids for mesoscale models. LAPS is designed for efficiency, specifically to enable real-time numerical weather prediction on affordable computers. For example, it runs on AWIPS, which is the weather forecasting workstation used by the US National Weather Service in all of its forecast offices. One very attractive reason for using high-resolution mesoscale models is to avoid using parameterizations of deep convection. Algorithms of this type detect conditions suitable for deep convection and then adjust the model’s vertical profiles of moisture and temperature to resemble post-convective environments. Surface precipitation is diagnosed as a result o