Synonyms for clear up

verb

1. To become clear; said especially of weather

   clear, blow over, stop raining, stop snowing, stop storming, lapse, run its course, pass, pass away, die down, pick up, lift, break, become fair, become sunny, brighten, burn off; see also improve 2.

2. To make clear

   explain away, clarify, resolve, settle; see explain, solve.