Thank you @idefix37 and @TheRadarGuy for your informative answers.
Also, one more question. On the interface, is there any indication which model run the data is using? Like shouldn't it say, "ECMWF 9km - 12z 01/22" for example (where it says "ECMWF 9km"), so we know which run the data output is showing? Perhaps I am missing this somewhere.
As for the geopotential height data, are the isohypes arbitrary? Shouldn't they be every 60 meters as standardized (540, 546, 552 decameters for example, or 5400, 5460, 5520)? They appear random. Perhaps the code needs to be arbitrary for the user interface?
Thanks again!