Americans celebrated 236 years of independence in spectacular style on Wednesday with dazzling displays of fireworks held across the country.

Though many of the festivities were cancelled or scaled down due to weather-related power outages and wildfire concerns, it was business as usual in New York as the Manhattan skyline was lit up to the delight of the thousands who lined the streets and millions watching at home.

Despite a day-long heat warning, thousands of revelers flocked to Manhattan’s west side to view the incredible Macy’s fireworks display, where a feat of pyrotechnics erupted over the Hudson River.

Meanwhile, millions at home watched Katy Perry giving a star-spangled performance in the Brooklyn Navy Yard, donning her uniform of a purple ponytail and an American flag mini-dress and singing the aptly named hit Firework. Country music sensation Kenny Chesney also performed.

Both performances were pre-recorded so as to avoid any snafus with inclement weather. The night’s events were MC’d by none other than Regis Philbin, who has been in retirement from Live With Regis and Kelly.

Crowds lined up early in the day along FDR Drive on Manhattan’s west side, despite a heat advisory and the promise of thunderstorms. But the weather held fast, and by sundown, temperatures were down to a cooler 86 degrees.

Americans celebrated 236 years of independence in spectacular style on Wednesday with dazzling displays of fireworks held across the country

Viewers along 12th Avenue witnessed as 40,000 fireworks in 15 dazzling colors and 30 separate shapes filled the sky in the half-hour spectacular.

But the storms had to go somewhere, and headed north to Boston. According to CBS Boston, the Esplanade was evacuated during the annual Boston Pops Fireworks Spectacular due to severe thunderstorms.

Jennifer Hudson was among those performing. The station notes that people were evacuated right before the 1812 Overture.

Hundreds of thousands from the Midwest to the Mid-Atlantic are spending the Fourth of July like America’s founders did in 1776: Without the conveniences of electricity and air conditioning.

Fireworks on the National Mall in Washington are planned to go forward, and in New York City, huge crowds lined the Hudson River to view the 36th annual Macy’s fireworks show.

Katy Perry giving a star-spangled performance in the Brooklyn Navy Yard, donning her uniform of a purple ponytail and an American flag mini-dress

In the nation’s capital, fireworks began shortly after 9:00 p.m. on the West Lawn. Entertainment was provided by Matthew Broderick, who performed two songs from the Broadway musical Nice Work If You Can Get It with Tony-nominated actress Keli O’Hara.

It was a mix of pop and classical in Washington, as the National Symphony Orchestra entertained with American classics like Tchaikovsky’s 1812 Overture with live cannon fire.

In Philadelphia, a dazzling fireworks show followed a 5,000-participant parade.

Singer Lauryn Hill performed days after pleading guilty to tax evasion, and the Roots also gave a rousing performance. Also performing were Queen Latifah, Common, and Joe Jonas of the Jonas Brothers.

Following the performances, fireworks were launched over the Philadelphia Museum of Art.

President Barack Obama marked the Fourth of July by thanking service members and their families, who he said “represent what is best in America”.

The president, accompanied by first lady Michelle Obama, hosted a barbecue and concert Wednesday for the families on the White House South Lawn.

Barack Obama saluted “this generation of heroes” for their service and sacrifice to defend American freedoms, specifically thanking them for bringing Osama bin Laden to justice and working to get out of Afghanistan.

He said the nation “will always be there for you, just as you’ve been there for us”. He said it was his promise, and America’s promise.

Afterward, the Obamas shook hands and posed for pictures with eager visitors. The U.S. Marine Band and country singer Brad Paisley performed.

Presumptive GOP presidential candidate Mitt Romney has spent most of the week off the campaign trail with his family in Wolfeboro, New Hampshire, but took time Wednesday to march in the town’s Fourth of July parade.

He was joined by his wife Ann; the two of them were seen participating in the parade, riding in trolleys, and greeting the crowds.

The former Massachusetts governor has been on vacation at his lake house -estimated to be worth over $10million – for the better part of the week.

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