Excessive heat accounts for an estimated 1,000 deaths annually in the U.S. NOAA's National Weather Service currently issues a suite of excessive heat products to provide the Nation advance notice of excessive heat events for the protection of life and property. These products are issued based on a single heat index value derived from temperature and humidity. Recent research has shown that often, a heat index value cannot fully predict when excessive heat becomes sufficient to stress a population causing a heat-related increase in mortality. A national Heat/Health Warning System (HHWS) based upon empirical data would provide the NWS with tailored excessive heat guidance related to actual mortality. This paper will describe how a national HHWS will provide a more accurate and standardized guidance system when warning the public of excessive heat events.