In the context of graphing, I would like to mention the UseNormalRainReference (and it's temperature equivalent UseNormalTempReference) inifile parameter. Few use it but it triggers interesting graph for the monthly Rain and Temprature graphs[1].
The values can be:
- Normal
- StationAverage
- Both
- None
In addition, if, for the raingraph, these values are set, one or two reference lines in the Daily Rain graph are plotted.
[1] : This requires the Normal values for your station to be filled in in CMX (NOAA Reports Settings=>Normal Mean Temperatures and =>Normal Precipitation