In 1967, the Bureau of Land Management in Alaska began producing isoline maps of buildup index by hand on a daily basis. These maps proved to be operationally valuable. In 1969, it was proposed that the isoline maps and other fire-danger ratings be produced by machine. By the middle of 1970, a complete fire-danger rating package, including isoline maps, was being machine-produced on a daily real-time basis and disseminated to a variety of users within 4 hours of observation time. This paper describes the system by which the data are processed, the form of the output, and the method of dissemination.