ACCESS City model (ACCESS-C) uses the ACCESS atmospheric model with 4km resolution to forecast for city-based regions in Australia. In this model, the vertical velocity (W)-based CAPE closure is chosen for model stability (avoid ance of grid point storms) for the forecasts in the Brisbane region where intense deep tropical convection often occurs along the coast line. In this closure, a vertical velocity threshold of 1 m/s is set. When the vertical velocity exceeds the threshold, the time scale for the CAPE closure is reduced to one third of the default value, and as a result, the parameterized convection scheme is more efficient in reducing the convective instability and the chances of a grid point storm.