The clash of seasons is underway as a "bomb cyclone" barrels across the United States.
So, what is a "bomb cyclone?"
Basically, it's a strong storm that strengthens rapidly-almost like an inland hurricane.
Winds from this storm have already been clocked at nearly 80 mph, equal to a Category 1 hurricane. More than 70 million people are at risk for severe weather, with half of the United States under severe watches or warnings.
Technically, it's a process called explosive cyclogenesis, or bombogenesis, when a weather system drops at least 24 millibars over 24 hours. Meteorologists use millibars to measure atmospheric pressure, and-as pressure drops storms get stronger.
Blizzard conditions are developing on the western side of the storm, with up to a foot of snow and very strong winds reported.
This storm will weaken as it moves towards Pittsburgh Thursday, bringing the threat for rain, a possible thunderstorm, and wind gusts of 40 mph.
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