Add weather settings and screen tint to map properties, so that weather/tint will take effect as soon as the map is loaded, and we don't need to set up parallel process events to do it every time.
Something similar to the Autoplay BGM might be good, where you can check the box and specify a new weather setting, or check the box but leave the weather as 'none', which just means it turns off the weather on the previous map. And the same for screen tint.
If developer wanted it to be conditional, they could then use parallel processes and conditions to override, just as they do now when they want a different BGM to play than the one specified on the map properties.