The excess heat factor (EHF) index was developed by Nairn and Fawcett in 2014 for use in Australian heatwave monitoring and forecasting. The index takes into account the idea that people acclimatise to their local climate, with respect to its temperature variation across latitude and throughout the year, but may not be prepared for a sudden rise in temperature above that of the recent past. However, the EHF is based only on the ambient temperature, which is not the only parameter to consider for assessing the human health effects of heatwaves. For instance, relative humidity plays a key role in the estimation of heatwave magnitude in humid regions, where its severity might be underestimated if metrics are temperature-dependent only. In this study, the EHF is determined separately for two heat stress indices that do consider the effects of humidity: apparent temperature, also known as heat index, and wet-bulb globe temperature. Hot events obtained from these two indices included in the EHF algorithm are compared to the original definition of EHF, with ambient temperature solely. Automatic weather stations from the Bureau of Meteorology covering a range of Australian climate zones are chosen in this analyses.