Water vapor across the globe on Jan. 3, 2018.Credit: NASA |
How does a system reach bomb-cyclone status? Its atmospheric pressure must drop so rapidly — at least 24 millibars in 24 hours, according to the National Weather Service (NWS) — that it explodes in strength.
"This can happen when a cold air mass collides with a warm air mass, such as air over warm ocean waters. The formation of this rapidly strengthening weather system is a process called bombogenesis, which creates what is known as a bomb cyclone," the NWS said.
The low-pressure system is moving near the Gulf Stream, which stays toasty all year. The temperature gradient between the two is amplifying the pressure drop, Roth said. Adding to this temperature difference is the orientation of the upper trough, or the low-pressure at about 30,000 to 40,000 feet (9,100 to 12,200 meters): This trough is negatively tilted (like a backward slant), which makes the system even stronger, Roth said.
During these bomb-cyclone events, winds can whip up fast, spinning toward the system's low-pressure center. Snow and blizzard conditions can follow, according to The Weather Channel.
"According to WPC [Weather Prediction Center] forecasts, the low is forecast to be 996 mb this evening (00 UTC Thursday) off the Carolinas and 960 mb off New England by Thursday evening (00 UTC Friday), a drop of 36 mb in 24 hours," Bryan Jackson, a meteorologist with the National Weather Service's Weather Prediction Center, told Live Science in an email.
In fact, on Friday, record-low temperatures are expected for most of the Mid-Atlantic and Northeast, where highs will hover in "the single digits and teens," the Post reported.