Andrew P Johnson / AP
Gabi Hogg, 7, and her mother Jenny Hogg share a moment before mounting a bike for the July Fourth Parade on Highway 77 in Panama City, Fla. Wednesday.
Millions of Americans headed for parades and fireworks shows on Wednesday to mark a sweltering Fourth of July holiday, some even celebrating as the nation's founders did -- without electricity.
Thunderstorms forced a brief delay in the annual Boston Pops concert and people on the Esplanade for the event were told to take shelter, NBC station WHDH of Boston reported. Two people were reported struck by lightning in south Boston around 11 p.m. but their conditions weren't known, boston.cbslocal.com reported.
CBS said three others were struck by lightning at Weirs Beach in Laconia, N.H., but their conditions weren't known.
Thunderstorms also threatened in the nation's capital, where thousands of visitors from across the continent took part in Independence Day celebrations.
Hosting the 32nd annual Capitol Fourth, "Dancing with the Stars'" Tom Bergeron told the audience how he was feeling the heat, exclaiming at one point that he was "sweating standing still."
Despite the heat, the usual enormous crowds flocked to the Mall and monuments throughout the day. By 7 p.m., the lawn of the Capitol where the concert took place was about two-thirds filled. Men and women lined the steps of the Capitol building and filled the balconies. The Capitol Fourth Concert ended with fireworks behind the Washington Monument.
Elsewhere, storm-ravaged states from Indiana to Virginia carried on celebrations on Day 5 of a power outage caused by deadly winds ripping through the region. More than 735,000 homes and businesses remained affected and thousands of utility workers stayed on the job in a scramble to restore electricity.
Erik S. Lesser / EPA
Americans celebrate 236 years of independence with parades, fireworks, hot dogs and family fun.
"We still have a tree on the garage. It's been one of those weeks," said Gary Belniak, 57, of Wheaton, Ill., who has been without power since Sunday. His town canceled its parade and fireworks display.
Exhausted by three sleepless nights in a house where temperatures hover at about 90 degrees, Belniak said he had all but given up on the holiday.
"I decided to come to work today. That's basically my Fourth of July. I'm so irritated," he said.
In hard-hit West Virginia, Karen Allen said she planned to spend the holiday - her sixth day without power - hunting for ice.
"I'm going to go look for ice, cold gold is what it is, it's very scarce," said Allen, 43, of Charleston, W.Va.
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That warmth coupled with dry conditions snuffed out annual firework displays in scores of towns and cities in the West that are reeling from deadly wildfires that charred hundreds of homes and displaced tens of thousands of people.
On the East Coast, tragedy struck when a cache of fireworks apparently accidentally exploded on the back porch of a family home in New Hampshire on Tuesday night, injuring nine people, including two young children with life-threatening injuries, according to Pelham, N.H., firefighter Shawn Buckley. The children, both under age 4, were airlifted to Boston-area hospitals, according to Buckley.
'Orange mushroom cloud': Fireworks explosion injures 9 at New Hampshire home
Narrowsburg, N.Y.: The bald eagle, the very symbol of American independence, brought down the show in the hamlet on the Pennsylvania border. The local fire department canceled its planned fireworks display after being warned by the U.S. Fish and Wildlife Service that it could face enormous fines and even prison if any nearby bald eagles were harmed. "We decided we're not going to take the gamble," said Fire Chief George Strumpfler, canceling the show that began more than 100 years ago. "It doesn't look like it's ever going to happen again."
Philadelphia: Ahead of a 5,000-participant parade and what was billed as the nation's largest free concert and fireworks display in the nation's birthplace , Mayor Michael Nutter led a ceremony including a military fly-over, readings from the Declaration of Independence and 13 people, representing the 13 original colonies, becoming naturalized U.S. citizens, NBCPhiladelphia.com reported. The Roots was the house band for the Philly 4th of July Jam on Wednesday evenng, with the band’s drummer, Ahmir “?uestlove” Thompson serving as musical director. The concert featuring Queen Latifah, Daryl Hall, Common and Joe Jonas and was followed by fireworks over the Philadelphia Museum of Art.
Out of wildfire's ashes, a July 4 extravaganza rises
President Obama greets U.S. service members while hosting a naturalization ceremony to declare them American citizens.
Chicago: The Windy City suffered through sweltering heat. The Navy Pier was the viewpoint for fireworks synchronized to music over Lake Michigan. The city-sponsored Grant Park show was canceled due to budget cuts.
Reuters, The Associated Press and msnbc.com's Jim Gold contributed to this article. Follow Jim Gold at msnbc.com on Facebook here.
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