If the weather in the picture is good, is it possible to be good? Is that a real conditional sentence in English? You don't have to use subjunctive mood.

Absolutely. The first tone is subjective. If you are in the same sky as the speaker, and you think it will be sunny tomorrow, you can say if it will, regardless of his fantasy/virtuality. Secondly, virtual reality depends on the situation. If it is not sunny at all, the speaker will think it is fantasy. If it looks sunny there, he will say whether it will.