Related Clues:

• Four-alarmer, e.g.
• Conflagration
• Go berserk
• Mark, as a trail
• Spew lava
• Let off steam?
• Burst forth
• Go boom
• Hit the ceiling
• Blow one's lid
• Cease being dormant
• Lose one's temper
• Go off violently
• Dazzling display
• Five-alarmer, e.g.