Proposed major format change to geomagnetic activity reports and forecasts produced by the SESC,Boulder, Colorado,U.S.A.

The Space Environment Services Center (SESC) provides real-time information on the state of the solar-terrestrial environment. In particular, the geomagnetic field is closely monitored. Summaries of geomagnetic activity are issued daily, as are forecasts for each of the next three days. Customers are alerted when activity rises above selected thresholds of theK- andA-indices. This present geomagnetic reporting and forecasting format is no longer the most appropriate for the expanding number of agencies and industries which the SESC serves. These customers need more detailed information about the geographic distribution of geomagnetic activity stated in plainer language. The proposed new format would quantitatively describe geomagnetic activity in terms of 6 qualitative categories: quiet, unsettled, active, minor storm, major storm, and severe storm. Summaries and forecasts would be made for 2 specific latitude zones: mid-latitudes (20–50 deg geomagnetic) and high-latitudes (50–80 deg geomagnetic). The format adapts well to longer-range (27-day) forecasts.