I basically built a while ago a pretty bloat system that does it by seasons etc. each day has lowest and highest point, but it's not perfect, the temperature can sometimes jump at the high from -8 to 0, which is pretty bad. This system isn't built via Advanced Random. I didn't implement the entire year so that days blend into each other but yes, now that is more relevant so I really need it, they should also blend at midnight (i think midnight is the most appropriate?).
The system is under event sheet time_temp_seasons, but it doesn't do much for the new one I wanna build.
In the new one it should first calculate it for the entire year:
And then each day at midnight it should calculate it for the day:
Did try using lerp but it's too perfect and not like the curves in the pictures above. I probably over-complicated it