NCEP EMC/MMB currently runs several parallel forecast systems for NAM, which is operational NAM. NAMB and NAMX are 12 km NAM parallels and NAMU is 4 km nested NAM over CONUS. This site displays cyclone tracks derived from the model forecasts. Choose model name for individual model tracks and choose "all models" for combined tracks. The tracks start from September 1, 2010 and run twice a day at 00z and 12z. Tracks in NAM are from operational runs. The tracks remain on the server for 45 days.