A swath of the US East Coast, including New York City, was under alert Saturday, as storm Henri was upgraded to what could be the first hurricane in 30 years to hit New England.

Forecasters warned of violent winds, heavy rainfall, the risk of flash floods and surging seas as the storm churned in the Atlantic, packing maximum sustained winds near 75 miles (120 kilometers) per hour.

Nasty weather that preceded Henri forced New York City to halt its star-studded Central Park concert that was billed as a "homecoming" for a metropolis hard hit by the pandemic.

The approaching hurricane had prompted New York Governor Andrew Cuomo to announce a state of emergency and the deployment of 500 National Guard soldiers in anticipation of response efforts.

"It's as serious as a heart attack," he warned.

He said the storm was expected to make landfall on Long Island, home to the plush Hamptons villages where wealthy New Yorkers retreat in summer, around noon (1600 GMT) on Sunday.

"It will be about a 26-hour event," Cuomo added, telling New Yorkers to expect "significant power outages" and "significant flooding" in some suburbs of the Big Apple.

Henri was anticipated to miss New York City by miles, but it could still cause tropical storm conditions beginning Saturday night.

Some of that weather rolled in during the concert in Central Park, and an announcer cut off Barry Manilow mid-song to urge revelers to proceed swiftly but calmly to the nearest exit.

"I guess for safety it makes sense. I mean I can hear the thunder," said attendee Maria Fuentes.

- 'Begin storm preparations' -

The US National Hurricane Center warned of "a dangerous storm surge, hurricane conditions and flooding" in areas of southern New England and Long Island, confirming in its 11 pm (0300 GMT) advisory that the storm continued to steam north at more than 20 mph.

The National Weather Service said late Saturday Henri was expected to remain a Category 1 hurricane at landfall.

Henri is expected to produce three to six inches of rain (7.5 to 15 centimeters) across the region, with isolated maximum totals near 10 inches, the NHC warned.

The heavy rainfall "may result in considerable flash, urban, and small stream flooding" as well as river flooding, it added.

Extreme weather events are becoming more frequent as temperatures rise.

Officials in New England -- which includes Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island and Vermont -- have warned people to get ready.

"All residents are advised to begin storm preparations today, and to pay close attention to local weather," the office of Massachusetts Governor Charlie Baker said Friday. 

His state, which will close parks and beaches from Saturday to Monday, was bracing for the high winds to knock out electricity for up to 300,000 locals, the governor's office said.

If Henri stays on its current course and maintains strength, it would be the first hurricane to directly hit New England in 30 years.

"The last hurricane to make landfall onto New England was Hurricane Bob in 1991," Dennis Feltgen, an NHC spokesman, told AFP. That storm killed at least 17 people. 

It has been almost a decade since such severe weather threatened the region.

"The last time we had hurricane watches issued for the area was for Hurricane Irene, back in late August of 2011," tweeted the National Weather Service in New York City.

The last hurricane to make landfall in Long Island was Gloria in 1985.

New York beaches were ordered closed for swimming Sunday and Monday as officials warned of high winds and possible storm surges, as well as flash flooding on roads.

The warnings have reignited memories of Hurricane Sandy, a more powerful storm that knocked out power for much of Manhattan and flooded subways in 2012.

Hurricane Grace kills 8 in Mexico

Hurricane Grace killed at least eight people, including five children from the same family, as it tore through eastern Mexico Saturday, causing flooding, mudslides and damage to homes and businesses.

The storm made landfall in Mexico for a second time near Tecolutla in Veracruz state as a major Category Three storm with winds of 125 miles (200 kilometers) per hour.

It later fizzled out as it moved inland over the central highlands, but not before causing widespread damage.

In the Veracruz state capital, Xalapa, streets were turned into muddy brown rivers.

Seven people died there and one more in the city of Poza Rica, Veracruz Governor Cuitlahuac Garcia told a news conference.

The victims included a mother and five of her children, who were buried when a hillside collapsed on their small home.

"I heard a bang on the roof and I went out to look," said their father Adan Moreno, who witnessed the tragedy.

"I heard the earth collapsing. The hill was swept away and they were all down there --  my wife and six children," he told AFP, his voice breaking.

He dug through the mud with the help of relatives but only one child was pulled out alive.

His wife and five other children, including a two-week-old baby girl, did not survive.

- 'It's destroyed' -

The streets of Tecolutla, home to about 24,000 people, were littered with fallen trees, signs and roof panels.

Esteban Dominguez's beachside restaurant was reduced to rubble.

"It was many years' effort," he said.

"Over there was my house, but it's destroyed. I'm left with no roof or furniture," he said.

Many homes in the region were left without electricity.

Grace dissipated as it churned inland, drenching Mexico City, but could develop into a new cyclone next week in the Pacific, according to the US National Hurricane Center.

The Mexican authorities remained on alert due to the threat of rivers overflowing and landslides, mainly in Veracruz.

President Andres Manuel Lopez Obrador offered his condolences to the families of the victims. 

Nearly 8,000 civil defense members, soldiers and electricity board workers had been put on standby ready to tackle the aftermath of the storm, he said on Friday night.

Authorities in Veracruz state said they had prepared 200 storm shelters and urged residents to hunker down in safe places.

They closed most highways in Veracruz, which is crossed by numerous rivers.

- Fishermen affected -

In preparation for the storm, workers along the coast boarded up windows to protect stores, fishermen brought their boats ashore and residents secured their homes after stocking up on canned food and water.

"We will spend many days without fishing -- almost a week," said Isabel Pastrana Vazquez, head of Veracruz's federation of fisheries cooperatives.

"About 35,000 fishermen will be affected because we can't go out," he said.

In Casitas, a small tourist town on the coast, fisherman Domingo Hernandez said the roof had been ripped off his home.

"The whole sheet was blown off. I was there holding it," he said, expressing relief that his boat was not damaged too.

The hurricane had already lashed Mexico's Yucatan Peninsula earlier in the week, forcing thousands of tourists to hunker down in shelters but blowing through with no loss of life.