This represents manual subjective coding of NWS radar echoes onto a regular MDR radar grid. Each grid box is 48 km on a side and the resulting grid covers the United States, lower Canada, northern Mexico, and the Gulf of Mexico. Each reporter at a radar site determines the maximum radar echo intensities for each box within its domain and reports this information as part of a SD report. This report also contains precipitation type, location, movement, coverage, change of intensity, cloud tops, and any special radar information.