After you toggle the "CompTm" button on, the NSHARP Skew-T and hodograph display compares all active times for the current station and source. The text in the time column is color coded to match the colors of the Skew-T and hodograph traces.
The left/right arrow keys step through time. The up/down arrow keys cycle through stations. The shift + up/down arrow keys cycle through sources.
Limiting frame counts can help manage large numbers of soundings in compare time mode.