A massive winter storm has roared down the US and Canadian east coast, forcing the closure of schools, businesses and the cancellation of thousands of flights.

National Weather Service (NWS) meteorologist Dan Peterson said record low temperatures were predicted for 28 major cities across New England, eastern New York and the mid-Atlantic states by Sunday morning.

The storm, threatening to dump half a metre of snow from the Carolinas to Maine, Boston, was expected to be followed immediately by a blast of face-stinging cold air that could break records in more than two dozen cities.

The NWS said Portland, Maine, and Burlington, Vermont could see minus 28C as state and local officials urged people to stay home so crews could clear away the snow.

There were concerns in Boston and elsewhere that if roads were not properly cleared, the snow could freeze into cement-like ice after the cold blast arrives.

Blizzard warnings and states of emergency were in wide effect, and wind gusts hit more than 113 km/h in some places.

Dubbed a ‘bomb cyclone’, the winter storm began on Thursday in the Gulf of Mexico and first struck Florida.

Nearly 500 members of the National Guard were activated on the coast on Thursday night to assist with the emergency response, including 200 in New York state, the US Department of Defence said.

New York City declared a “Winter Weather Emergency” with both La Guardian and JFK airports and the city’s main ferry service were temporarily suspended.

A Winter Weather Emergency has been declared in New York City. Watch: pic.twitter.com/kG4HiReDAo @NYCMayorsOffice

— City of New York (@nycgov) January 5, 2018

Eastern Massachusetts and most of Rhode Island braced for as much as 7.5cm of snow per hour as high winds caused coastal flooding from Massachusetts to Maine, overwhelming fishing piers, streets and restaurants.

The rising waters also stranded people in homes and cars.

More than 100,000 homes and businesses lost power at some point, depriving many people of heat. Connecticut opened more than 100 warming centres in 34 towns.

More than half of the outages – mostly in the South – were restored by Thursday afternoon.