Will storm be a 'bomb cyclone?' Time will tell, forecasters say

A possible "bomb cyclone" could strike the tristate area early Saturday, which means the snowstorm that starts Friday could rapidly strengthen, the National Weather Service said.

These powerful types of storms occur when a mass of cold air "collides" with a warmer mass of air, which may derive its heat from the ocean, the weather service says.

Right now, there is the potential for a bomb cyclone because a high-pressure system with frigid air is forming over eastern Canada — just as its opposite, a low-pressure system, develops over the mid-Atlantic and Carolinas, said Tiffany Fortier, an Upton-based weather service meteorologist.

So what really matters, Fortier said, is how these two systems interact. That also will help "steer" the storm, she said.

A track farther west brings more snow; to the east will bring less. "Our models still are fighting over that," she said Thursday morning.

To qualify as a bomb cyclone, the air pressure in the center of a low-pressure system must plunge dramatically within 24 hours. This phenomenon, called "bombogenesis," would bring an explosive intensification of the storm, boosting its winds and precipitation as the system swirls counterclockwise and sends snow back at the coast, according to meteorologist Matthew Cappucci of The Washington Post.

"There’s a lot of uncertainty; it’s still iffy," Fortier said. "So we don’t want to just throw the word out there so easily."