0:34ABC NewsWeatherDecember 21, 2022What is a 'bomb cyclone'? It occurs when the pressure of a storm drops at least 24 millibars in 24 hours.Up Next in newsMajor winter storm moving across the country with heavy winds and snowDecember 21, 2022Winter alerts in effect across Northeast December 17, 2022Nationwide storm now blasting NortheastDecember 16, 2022