The appended forecast files consist of a special time extraction of the previous seven (-48 hr) forecast cycle files to create a series of pseudo-analysis (0-hour initialization) and short-time (+3 h or +1,+2,+3,+4,+5) forecasts that have been appended to each other to create a continuous data time series for the previous 48 hours in a single file.
These special time extracts are only available for the following files.