Boil over
Else clues• Act like a volcano
• Appear suddenly
• Become active volcanically
• Become active, as a volcano
• Become unmanageable
• Become violent
• Become violently active
• Blow
• Blow a fuse
• Blow a fuse, say
• Blow a fuse, so to speak
• Blow a gasket
• Blow like a volcano
• Blow like Mauna Loa
• Blow one's lid
• Blow one's stack
• Blow one's top
• Blow up
• Blow, as a volcano
• Blow, like Dante's Peak
• Blow, like Etna
• Blow, volcano-style
• Break out
• Break out in hives
• Break out, as fighting
• Break out, as in a rash
• Break out, as violence
• Burgeon
• Burst
• Burst forth
• Burst open
• Burst out
• Cease being dormant
• Completely lose it
• Do as Pinatubo did
• Eject lava
• Emerge violently
• Emulate a geyser
• Emulate a volcano
• Emulate Dante's Peak
• Emulate Etna
• Emulate Kilauea
• Emulate Vesuvius
• Explode
• Explode like Pinatubo
• Flare up
• Fly off the handle
• Give vent to anger
• Go ballistic
• Go berserk
• Go boom
• Go nuts, as a crowd
• Go off
• Go off like Mount St. Helens
• Go off like Vesuvius
• Go off violently
• Go off, as a volcano
• Gush, as a volcano
• Have a big inning
• Hit the ceiling
• Hit the roof
• Let lava loose
• Let loose
• Let off steam?
• Let out lava
• Let out the lava
• Lose control
• Lose it
• Lose one's cool
• Lose one's temper
• Make like Mount St. Helens
• Mauna Loa may do it
• Overflow with lava, say
• Really lose one's temper
• Show one's rage
• Spew
• Spew forth
• Spew lava
• Spew like Stromboli
• Spew magma
• Totally blow?
• Unleash pent-up emotions
• Vent
• Vent, like Vesuvius
• Vesuviate
• What an active volcano may do