The historically high toll in human lives lost to natural disasters such as hurricanes, tornadoes, floods, and other progressive events signals the need for some type of personal warning that alerts people to the need to evacuate or otherwise protect themselves in the face of an advancing threat. Traditional warning services, which rely on broadcasts by the mass media in the metropolitan areas of the United States, achieve measurable success in disseminating warnings. However, warnings to isolated populations that exist in the U.S. and elsewhere in the world may be poor to effectively nonexistent, especially in the many archipelagoes. Earth Alert, a joint project of NASA Goddard Space Flight Center and Scientific and Commercial Systems Corporation, is targeted at development of a simple, low-cost means for providing timely warning to otherwise isolated populations. The project uses appropriate relay capabilities of U.S. satellites already in orbit, and thus avoids the high-cost development and launch of dedicated resources.