Why is the weather bomb so dangerous?
Difficult to predict and easy to confuse with other weather hazards, Explosive Cyclogenesis or, as often called, “The weather bomb”, constitutes one of the most interesting meteorological phenomena. Its basic scientific principle is a rapid fall in the central pressure of a depression. Due to the collision between warm Sub-tropical air and cold Artic air a massive release of energy that is converted into motion (wind) and temperature contrast is created which drives the jet stream. The bigger the contrast the faster the jet stream, creating a vacuum which causes a pressure drop and pressure gradient to increase, therefore wind to gain speed and storms to form.
In order to meet the criteria of an Explosive Cyclogenesis the pressure drop must be at least 24 mb in 24 hours. Scientific Meteorological researches show the upper trend of weather bombs in the Northern Hemisphere over the last years. Most of them agree that there is another dangerous situation added to the increasing trend which is associated with a rapid intercontinental air pollution transport.
These systems produce strong winds, heavy rainfall causing major floods and dangerous Oceanic conditions due to the rapid fall of pressure. These phenomena could be extremely hazardous to the environment and a dangerous situation for people.
One of the biggest tragedies related to Explosive Cyclogenesis is The Armistice Day Blizzard, 11th of November 1940 (USA). The “Weather bomb” pressure dropped 28.7 mb in 24 hours. These phenomena are very difficult to predict since the principle is similar to other extra tropical cyclones, but when it forms it does it relatively fast. The 11th of November 145 people died when caught unforeseen by “The Weather bomb”.
Source: Flight instructor Alba Dobargnes in Flying Academy