‘Bombogenesis’: Thousands of flights cancelled in snowstorm chaos

A powerful winter storm classified as a “bomb cyclone” has pounded the US, causing major flooding and power cuts. SEE THE DRAMATIC IMAGES.

A powerful winter storm classified as a “bomb cyclone” has pounded the US, forcing a mass cancellation of flights.

Parts of New England are bracing for what could be record snowfall as strong winds pushed seawater ashore in parts of coastal Massachusetts, causing street flooding.

“Hunker down for 24 hours, and sometime tomorrow, you’ll be able to go back out and resume some of your normal activities,” Tom Guthlein, Rhode Island’s acting director emergency management, said on Saturday (local time).

People shovel outside the Davis Square MBTA station during the snowstorm in Someville, Massachusetts. Picture: Getty

Snow on campus at Harvard University in Cambridge, Massachusetts. Picture: Getty

Snow hits the streets of Manhattan. Picture: Getty

A plough drives down Lower Sheep Pasture road shovelling snow in Stony Brook, New York.

The winter storm thrashed Manhattan and wreaked havoc in parts of Delaware, Maryland, New Jersey and Long Island.

Airlines cancelled thousands of flights for Saturday (local time) as the powerful winter storm hit major cities on the US East Coast.

According to FlightAware, more than 3500 flights within, into or out of the United States were cancelled, with East Coast hubs being the most affected.

The storm became a “bomb cyclone” — meaning the storm strengthened rapidly and had pressure drop a certain amount within 24 hours — the Weather Prediction Centre said.

More than 10 million people in some coastal areas from New Jersey into New England are under blizzard warnings, meaning heavy snow and strong winds will make for terrible visibility and dangerous travel.

Traffic moves through lower Manhattan in the pre-dawn hours as a winter storm brings heavy snow, freezing temperatures and blowing winds. Picture: Getty

As the storm wreaked havoc, a human chain was formed to rescue drivers trapped under a collapsed, snow-covered bridge.

Rescue workers rappelled 46-metres down to pull people from a bus dangling over above the ravine.

Three people were hospitalised and another seven were treated for injuries after the bridge collapsed into a snowy ravine in Pennsylvania.

Vehicles including a Port Authority bus are left stranded after a bridge collapsed in Pittsburgh, Pennsylvania. Picture: AFP

The area was evacuated for fear strong smells of gas hinted at a leak, prompting authorities to cut natural gas lines.

Images from the scene showed about five vehicles, including the bus, on the bridge.

The collapsed bridge is seen along Forbes Ave. At least 10 people were reportedly injured in the early-morning collapse, hours ahead of a scheduled visit by Joe Biden. Picture: AFP.

The bridge collapsed in Pittsburgh hours before US president Joe Biden was due to visit the city’s crumbling infrastructure.

The President “has been told of the bridge collapse in Pittsburgh,” Press Secretary Jen Psaki tweeted, and will “proceed with the trip planned for today and will stay in touch with officials on the ground about additional assistance we can provide.”

Vehicles including a Port Authority bus are left stranded after a bridge collapsed in Pittsburgh, Pennsylvania. Picture: AFP.

Blizzard warnings were in effect for 45 million Americans from North Carolina in the south to eastern Maine in the north.

The heaviest snowfall from Friday to Saturday night local time was predicted to drop up to 12 inches of snow from Maryland, across New Jersey and New York, to New England.

Massachusetts and New York braced for wind gusts between 72 km/h to 112km/h and temperatures dropping below -18 degrees Celsius.