A powerful nor’easter with 40 million Americans in its path has finally smashed into the East Coast on Friday night, sending seawater surging through streets and over seawalls. 

The first dramatic impacts were already unfolding after dark, with roads transformed into rivers from New Jersey to Maryland while raging surf crashed ashore in Rhode Island.

Thousands of customers were without power and hundreds of flights had been canceled as the sprawling storm began battering the coastline. 

Forecasters are warning some of the worst conditions were still to come.

A State of Emergency is in effect for New York City, coastal areas of New Jersey, Long Island, and Westchester County, New York, ahead of the strengthening and approaching storm.  

In Narragansett, Rhode Island, dramatic footage showed coastal flooding already underway around Narragansett Pier.

Seawater could be seen rushing over the seawall and spilling onto Ocean Drive, while pounding surf reached the Narragansett Town Beach parking lot inundating it.

Farther south on New Jersey’s Long Beach Island, residential streets disappeared beneath floodwater as the Atlantic surged inland.

In Ocean City, Maryland, seawater swamped entire streets Friday night as the powerful nor’easter began hammering the popular coastal resort

Long Beach Island in New Jersey appeared deluged by floodwaters as the sea washed inland

Footage showed water surrounding homes and swallowing roads, leaving mailboxes poking above the rising waterline. 

At Surf City Bay Beach, powerful winds whipped seawater ashore even before the storm’s strongest conditions had arrived.

And in Ocean City, Maryland, video recorded shortly before 10pm on Friday night showed seawater completely covering sections of roadway as the resort town began flooding.

The dangerous conditions offered a stark explanation for the decision to cancel the three-day Oceans Calling music festival as the storm closed in.

The nor’easter is expected to track offshore during the weekend, but forecasters warned it will pass close enough to the coast to unleash damaging winds, huge waves and significant coastal flooding.

Tens of millions of Americans are in the storm’s path.

The National Weather Service (NWS) warned particularly dangerous flooding could strike parts of the Mid-Atlantic coastline, with New Jersey and Delaware facing some of the greatest threats.

In Manasquan, New Jersey, water was already pouring onto roads as darkness fell on Friday night.

A State of Emergency is in effect for New York City, coastal areas of New Jersey, Long Island, and Westchester County, New York, ahead of the strengthening and approaching storm

Ocean City, Maryland was already battling significant coastal flooding late Friday, with surging seawater completely covering roadways as the storm churned offshore

Mailboxes could be seen peeking above the waterline in Long Beach Island, New Jersey

Officials earlier issued a voluntary evacuation for some of the community’s low-lying neighborhoods. 

Mayor Mike Mangan warned residents to expect ‘a lot of water in the streets for a long time.’

Sea Bright, another vulnerable New Jersey beach community, was preparing for flooding that could leave some streets beneath as much as six feet of water.

Mayor Brian Kelly urged hundreds of residents in low-lying areas to consider getting out while they still could.

‘It’s going to be worse than average,’ Kelly warned. ‘We do have probably one or two flooding events a year, sometimes more, sometimes less, but I think this one will be closer to an Irene-scale flooding event.’

He was referring to Hurricane Irene, which caused devastating flooding across the Northeast in 2011.

‘I hope I’m wrong, but that’s my gut feeling,’ Kelly added.

The town planned to open its recreation center to residents forced from their homes.

Meanwhile, forecasters warned winds could become ferocious farther north.

Members of the media set up for their dramatic live shots ahead of their evening news bulletins in Monmouth Beach, New Jersey before the storm comes ashore

Conditions seen in coastal Virginia earlier in the week, above, gave some indication as to what was to come for those along the East Coast 

North Carolina’s Outer Banks felt the brunt of a developing nor’easter

Peak gusts could reach between 60 and 65mph across Cape Cod, Martha’s Vineyard and Nantucket from Friday night into Saturday.

Boston could see gusts of 50 to 55mph, while inland communities could experience winds of 35 to 40mph.

Southeastern Connecticut and eastern Long Island could experience winds approaching similar speeds. 

‘It’s definitely going to be a case of the closer to the coast you are, the more impacts from the storm you’re likely to see,’ NWS meteorologist Matthew Belk said.

One particular concern is the timing. Although nor’easters are a familiar threat as New England enters fall, many trees are still covered in leaves.

Those leaves create greater resistance against powerful winds, potentially making trees and branches more likely to come crashing down.

That in turn raises the threat of blocked roads and widespread power outages.

Parts of coastal New Jersey, southeastern New York and southern New England can expect 4-8 inches

Wind gusts of 40-60 mph are forecast in the hardest-hit areas, with localized 60-80 mph gusts

Residents and beachgoers in Monmouth Beach, New Jersey, prepare for the nor’easter 

People gathered along the shoreline to watch large waves crashing against the coast in Monmouth, New Jersey

People came down to the beach to watch the waves crash ashore and the storm approached

Traffic passes beneath a sign over the West Side Highway warning of high winds and rain over the weekend with the impending arrival of a nor’easter in New York

Thee was a spectacular sunset on Friday night in New York with a rainbow forming ahead of the approaching torm

Travel was already descending into chaos. More than 200 flights involving airports in Boston, Nantucket, Martha’s Vineyard and New York were canceled on Friday, with further cancellations already scheduled for Saturday.

Several airlines were allowing affected travelers to change or cancel certain East Coast flights without the usual fees.

Ferry travel was also being hammered by the deteriorating weather.

Public ferries connecting Cape Cod with Nantucket and Martha’s Vineyard suffered widespread cancellations on Friday as strong winds churned the ocean.

Rhode Island ferries serving Block Island were also canceled, with disruption expected to continue on Saturday.

For island residents, getting stranded by brutal coastal weather is an occupational hazard.

‘It’s a nuisance, but you know, we know what to do with this kind of stuff at this point,’ said Sean Driscoll, a spokesman for the Woods Hole, Martha’s Vineyard and Nantucket Steamship Authority. ‘This is not out of the realm of ordinary.’

The storm also tore through weekend entertainment and sporting schedules.

The Boston Red Sox rearranged their series against the Chicago Cubs, shifting Sunday’s afternoon game to Friday as part of a split doubleheader.

Ed Sheeran canceled high-profile Friday and Saturday concerts at Gillette Stadium in Foxborough, Massachusetts, because of the dangerous conditions.

A surfer rides a wave during the start of the nor’easter storm in Gloucester, Massachusetts

Chuck and Teresa Palmieri move lawn furniture to a safe location at a relative’s seaside property as the Atlantic Ocean kicks up surf in Gloucester, Massachusetts

Brenda Malloy enjoys the nor’easter storm by the beach in Gloucester, Massachusetts

Surf breaks along the rocky coastline, with the twin lighthouses of Thatcher Island visible in the distance, during the early stages of the nor’easter on Friday in Gloucester, Massachusetts

In Gloucester, Massachusetts, Ashley Destino took advantage of the last hours before the storm to bring her two young children to the beach.

‘We came to the beach on Friday afternoon because we knew we were going to be inside all weekend,’ she said.

Destino prepared Legos and arts and crafts to keep her children, aged seven and four, entertained while the family hunkered down.

She also added extra lines to secure her boat, while her husband prepared a generator in case the power failed.