A powerful storm system in the northern U.S. intensified into a “bomb cyclone,” bringing blizzard conditions to the Plains and Great Lakes on Monday.

The storm rapidly strengthened due to a sharp drop in atmospheric pressure, a defining feature of bomb cyclones, according to NOAA.

Forecasters warned that an Arctic front colliding with warm southern air could create hazardous conditions, including snowstorms, thunderstorms, and unusually cold temperatures, CBS News has reported.

The system moved into the Northeast, producing lake-enhanced snow, high winds, and freezing rain.

Light rainfall is expected to follow through Tuesday morning.