What is a good simile for....?

We're not off to a very good start. "smells.... all around me" is incongruous. Mist, yes. Smells, no. Good similes depend upon the ability to verbalize a clear image in the first place, and from that image to mentally scroll through the possible comparisons. I suggest that if the purpose of this exercise is to produce a simile, that you create a scenario which does lead to a clear image for you. If the purpose is story-telling, then avoid the simile and say something like, "The smell of moisture in the air from the cloudburst the night before was overwhelming. I smelled not air but earth, as though I were a newly-buried corpse."