I'm a bit unsure about what I can get away with in past tense, regarding time. Sentences containing "now", "soon", etc. Example: "Now it rained." It's obviously past tense because of "rained", but is it bad style to have the "now" in there? "But soon the sky would clear up." is really just guesswork about a near future, from the POV of the narrator, but still in past tense. Bad style? It seems necessary in cases where the narrator talks about things that happened before, during or soon to be happening, from the time of the POV.