From Longman Dictionary of Contemporary Englishflash flood/fireflash flood/fireFAST/QUICKa flood or fire that happens very quickly or suddenly, and continues for only a short time → flash
Examples from the Corpus
flash flood/fire• Summer flash floods achieve little beyond destroying crops.• The report warns of extreme events such as thunderstorms causing flash floods and intense meteorological depressions.• Urgent talks after flash flood causes chaos.• Like the desert after a flash flood, Freshers' Fair is decorated by societies which bloom for just a day.• He believes Ruess probably died in a flash flood or fell off a cliff.• In the event of a flash flood, remember that you should immediately seek higher ground.• A couple of years ago these lanes were far from peaceful when a flash flood swept through the area. 