isolines of temperature

[RJohnson]

What is the source for temperature isolines? It's a very useful visualisation but I've discovered now that it's quite imprecise compared to reality - unusable really, disappointing.
Perhaps it was only for show, was I wrong to expect this to be correct?

[idefix37]

@RJohnson
The source of temperature isolines is the same as the one used to draw the colored layer for temperature and to display the local temperature in the weather picker.
But the method used by Windy to draw these isotherms tends to smooth them out. So they are more useful on a large scale.
In addition, at a local scale you must take into account the resolution of the model which does not allow for sufficient granularity, for example in mountainous areas.