What is a ‘bomb cyclone’? US ravaged by historic deadly winter weather

More than 50 people have died in the US as an Arctic blast pummeled North America with extreme cold, blizzard conditions and high winds

An Arctic blast is sweeping the United States, impacting swathes of the country this holiday season with a miserable mix of dangerous cold, blinding snow squalls and flash freezing.

The powerful winter storm began to produce widespread, disruptive and crippling impacts across the central and eastern United States and Canada just before the Christmas period, and continues to create chaos as the new year approaches.

As of Wednesday (28 December) at least 55 people have died as a result of the extreme weather in the US, and the death toll is expected to keep climbing.

Buffalo, New York, has been by far the hardest-hit region as bomb cyclone conditions left at least 31 people dead in Erie County.

The harrowing weather phenomenon “bomb cyclone” is technically called bombogenesis and whether it occurs all depends on how quickly the pressure drops.

As the jet stream pushes very cold air down from the Arctic and into the US, this mass of frigid air bumps up against the warmer air ahead of it.

If the atmospheric pressure falls rapidly over a period of 24 hours, it can become a serious storm otherwise known as a “bomb cyclone”. They typically occur over water due to the high levels of warmth and moisture so it is a rare event if a bomb cyclone happens over land.

Buffalo has been hammered by more than 50 inches of snow since the storm struck, with nearly four feet falling by Christmas.

The death toll in Erie County - which includes Buffalo - rose to 31 late on Tuesday, marking the deadliest storm in western New York in at least two generations.

State and military police have now been sent to Buffalo to enforce a driving ban so that officials can clear the snow and people stranded in cars and homes can finally be reached.

As the city continues to dig out of the storm, the death toll is expected to climb further.

Beyond New York state, winter storm Elliott’s icy bite also saw temperatures plunge to record lows in parts of Montana, Pennsylvania, and Wyoming, and wrought havoc on Christmas travel plans.