Context: Recently, National Weather Service confirmed that snow had intensified into a “bomb cyclone” in eastern United States.

About bomb cyclone

• A bomb cyclone is a type of storm that typically develops in the wintertime, over the ocean or off a coast.
• It becomes a bomb when its central pressure decreases very quickly—by at least 24 millibars in 24 hours.
• It begins in the temperate latitudes and strengthens fast, with the atmospheric pressure at its center dropping swiftly, a process now called “bombogenesis.”
• Most cyclones don’t intensify rapidly in this way. Bomb cyclones put forecasters on high alert, because they can produce significant harmful impacts.

How is a Bomb Cyclone formed?

• There are many reasons cited for the formation of Bomb Cyclones. Out of these the principal mechanism for its formation has been cited as baroclinic instability. 
• But even this principle mechanism has been subjected to debate amongst the scientific community as many case studies conducted over this matter have proven otherwise.

There are other factors in play as well such as

• Deep tropospheric frontogenic processes which occur both during upstream and downstream of the cyclon’s surface
• Influence of air-sea interaction
• Latent heat release

In which region does a Bomb Cyclone occur?
There are four active regions which are hot spots for Bomb Cyclone:

• The Northwest Pacific
• The Northern region of the Atlantic Ocean
• The Southwest Pacific
• The Southern region of the  Atlantic Ocean.

About Bombogenesis

• The word “bombogenesis” is a combination of cyclogenesis, which describes the formation of a cyclone or storm, and bomb.
• This can happen when a cold air mass collides with a warm air mass, such as air over warm ocean waters.
• It occurs when a midlatitude cyclone rapidly intensifies, dropping at least 24 millibars over 24 hours.
• Bombogenesis is fairly common in the Pacific Ocean region because there is enough water surface area for strengthening.
• It has happened a few times on the Atlantic coastline; however, it is not as common there.