Blow up is a common phrase used to describe sudden bursts of anger, high-pressure situations and explosive devices. However, there are many synonyms that can be used instead of "blow up" to add more variation to your writing or speech. For example, "explode", "erupt", "ignite", "burst out", "seethe", "lose one's temper", "snap", "freak out" or "go ballistic" can be used to convey the idea of someone becoming angry in an instant. In terms of large-scale destructive events, one can use expressions such as "go up in flames", "implode", "detonate" or "blowout". These synonyms can help you express ideas more vividly and accurately.