Determination of the Highest Cloud Top in SAS Scheme and Its Impact on Hurricane Forecasts

Cumulus convection parameterization scheme (SAS) has large impact on hurricane track and intensity forecasts. Specifically, the calculations of 1) highest cloud top and 2) cloud base mass flux give large differences in hurricane track and intensity forecasts in HWRF model. The determination of the highest cloud top depends on the parcel buoyancy calculation, which strongly depends on the assumptions of the entrainment and detrainment of the rising parcel. We will discuss several different methods of calculating the highest cloud top and compare their impacts on hurricane track and intensity forecasts in HWRF model.