Bombogenesis: When a Surface Low “Explodes”

Often, you may hear the term "bombogenesis" or "bombing out" used to describe a storm. While the name sound sensational, and perhaps threatening, it's a true meteorological term used to define a rapidly intensifying storm system.

At face value, the term means the creation (genesis) of a bomb (deep cyclone). Meteorologically, it occurs when the center of low pressure drops 24 millibars in 24 hours. This is purely a meteorological definition. Although the impacts of a bomb cyclone can be great, it does not guarantee it.  Location of the storm, track, area affected will all be different with each "bomb cyclone".

A millibar is a unit of measurement to measure atmospheric pressure. Pressure rises and falls naturally in the atmosphere due to changes in temperature or dynamics in the atmosphere. Often, when a storm system goes through bombogenesis, you will find sharp contrasts in surface temperatures, as well as upper level atmospheric forcing dynamics that aid in rapid intensification of a storm. One example of forcing dynamics occurs under powerful troughs (dips) in the jet stream, which causes rising air. As air rises away from the surface, a low pressure center is created or deepens.