Look at these sentences:
To talk about the weather in French, you will use Il y a + du / de la / de l' / des + noun. (Literally: there is some ...).
Note that du / de la / de l' or des agree with the noun following.
Case of il fait du soleil or Il fait soleil: This seems to be presented as idiomatic in a lot of French learning methods, and to be perfectly honest, some French people use it. However, it is not good French and still sounds clunky and child-like to many French ears (including mine!).
Il fait should always be followed by an adjective, and il y a used with nouns.
Note that you could also use Le temps est + adjective (ensoleillé, pluvieux, nuageux, brumeux, orageux) instead of using il y a + noun.
BUT there is no adjective for brouillard (fog), or vent (wind).