The very real scientific term describes a storm that suddenly intensifies following a rapid drop in atmospheric pressure. Bombing out, or "bombogenesis," is when a cyclone's central pressure drops 24 millibars or more in 24 hours, bringing furious winds that can quickly create blizzard conditions and coastal flooding.
It's actually not that rare a phenomenon; meteorologists estimate these kinds of storms break out in the Northern Hemisphere about 10 times a year. They can go by other names, like Nor'easter and mid-latitude cyclone, which may explain why you've never heard of one before Winter Storm Grayson started dumping snow in Tallahassee on Wednesday morning. But Grayson isn't your typical bombogenerator.
It's what happens when everything comes together just right (or just wrong). Grayson is expected to explode up the East Coast between now and Friday, intensifying as it makes its way from Florida to Nova Scotia, blowing record snowfalls around at category 3 hurricane wind speeds.