Storm Dennis explodes into ‘bomb cyclone’ as it roars toward UK, northern Europe (Source

 AccuWeather)Storm Dennis, which developed into a formidable “bomb cyclone” early Thursday, will bring dangerous winds and flooding to the hard-hit United Kingdom and northern Europe this weekend just days after deadly Storm Ciara triggered widespread travel disruptions. Becoming the fourth-named windstorm of the season by collaboration of Ireland, the United Kingdom and Netherlands, Dennis was officially named by the UK Met Office on Tuesday. Windstorm season in Europe traditionally runs from September through the end of April. Dennis became classified as a bomb cyclone Thursday morning after the central pressure of the storm dropped 1.38 inches of mercury (46 mb) in 24 hours. The drop was recorded from 29.4 to 28.1 inches of mercury (996 mb to 950 mb).  This incredible drop in pressure is almost two times greater than what is needed to be considered a ‘bomb cyclone,’ which is defined by meteorologists as a pressure drop of 0.71 of an inch of mercury (24 mb) over a 24-hour period.