"Awesome!" exclaimed Ben Fedak, a Queens musician taking in the show with his brother Peter, as dazzling green shells exploded above him. "This is the best fireworks show that I've ever seen." The 30-minute show was billed as the nation's biggest, with 40,000 fireworks. For the display, eight barges on the East River and at the South Street Seaport set off an average of 1,300 shells per minute.

The program featured musical performers as part of the nationally televised broadcast, including Martina McBride, Joss Stone and "American Idol" winner Jordin Sparks. Organizers estimated about 3 million people withstood the soggy weather to line up and watch the pyrotechnic extravaganza, about the same number as the year before, when 8 million watched on television. The organizers had called their fireworks show "waterproof."

The threat of storms forced officials in several eastern Pennsylvania cities to postpone fireworks shows, while dry weather curtailed some celebrations elsewhere. Breckenridge, Colorado, canceled its fireworks show because of the high fire danger. In Washington state, private fireworks were banned in Seattle, Tacoma and parts of Spokane.

In the South, some cities across Georgia considered canceling fireworks displays because of a drought, but two big shows stayed on the schedule for Atlanta. A tornado warning around 5 p.m. in Washington's suburbs prompted authorities to evacuate the thousands of people gathered at the National Mall for a holiday concert and fireworks. Authorities reopened the Mall a couple of hours later.

The festivities and patriotic observances took place under heightened security in the aftermath of the attempted car bombings in Britain. Hundreds of officers from about 20 law enforcement agencies were on duty in Washington. Visitors were required to pass through 19 security checkpoints.

Security measures at the New York region's tunnels, bridges and airports remained heightened following failed attacks on Glasgow and London last week, and no additional precautions beyond those already in place were taken for the holiday, said Marc LaVorgna, a spokesman for the Port Authority of New York and New Jersey.