The phrase "blow itself out" can be used to describe a situation or event that eventually subsides or comes to an end on its own. There are several synonyms for this phrase that can be used depending on the context and tone of the conversation. Some common synonyms for "blow itself out" include "fizzle out," "die down," "taper off," "subside," "run its course," "come to an end," and "cease." These synonyms can be used in various situations, such as when discussing a storm, a disagreement, a political issue, or any other event that calms down or ends naturally over time.