Record-breaking heat and oppressive humidity made people across the eastern half of the country miserable Wednesday and sent tourists in the nation's capital scrambling for relief in the cool marble halls of Capitol Hill.

Others forced to work outdoors guzzled icy drinks to cope with the heat wave that has sent temperatures soaring over 100 across the East and parts of the Midwest.

"This is unbelievable," said Bob Garner, a tourist from Atlanta who retreated with his family into the air-conditioned comfort of the Capitol. "They get the hottest days of the year while we're here."

Click here to check out FOXNews.com's heat wave photo essay.

A high of 100 was forecast in Washington. With the humidity, it was expected to feel like 113. By midafternoon, the mercury had climbed to 97. It was even hotter on the steaming pavement downtown.

In New York, the temperature rose to 101 at LaGuardia Airport and 96 in Central Park. Baltimore, Boston and Philadelphia also expected to hit at least 100, and the heat could linger through much of Thursday.

Click here to read more about how New Yorkers are dealing with the heat.

At the Capitol, tourists filled water bottles at drinking fountains and doused themselves. Others drenched their baseball caps before putting them on.

At the Library of Congress daycare center, children stayed inside because it was deemed too hot to swim. Washington Redskins coach Joe Gibbs cut his players a break by ending afternoon practice early and then pushing back the 4 p.m. session to 7 p.m.

"It's unbearable, it's oppressive," said Joy Haber, 44, who canceled a trip from Long Island into Manhattan because of the stifling weather. Her 13-year-old son, Sean, skipped day camp when his bus arrived with a malfunctioning air conditioner.

The Dixie Chicks postponed their Wednesday night show at the outdoor Jones Beach Theater on Long Island because of the scorching heat.

In Philadelphia, concrete worker Bob Ferguson was building walls 32 feet below street level. "Down in that hole, there's no air," said Ferguson, who wore the mandatory hard hat, long sleeves, long pants and work boots.

Bicycle messenger Gravett Dhuja tried to look at the bright side as he rested near a Capitol Hill office building: "It's been hot, but rain is a lot worse for us."

The same heat wave was blamed for as many as 164 deaths last week in California.

In Boston, authorities awaited autopsy results on a pregnant woman who died Saturday after collapsing at a sweltering Red Sox game. Denise Quickenton, 29, suffered an apparent heart attack after sitting in sunny bleacher seats where the temperatures was at least 90 degrees, authorities said. She was seven months pregnant, but a medical team was able to deliver her 4-pound infant at a hospital.

A 15-year-old high school football player died in Georgia, one day after collapsing in the heat at practice, and the heat was suspected in the death of a 75-year-old woman in Wisconsin who kept the air conditioning off to save money. An 18-month-old boy was also found dead inside a van in Kentucky.

Click here to read the story about the football player.

Click here to read the story about the 18-month-old boy.

Some Washington tourists pressed on with their plans, gulping bottled water and fanning themselves with brochures outside such landmarks such as Union Station and the Washington Monument.

"The humidity is so bad — not like in Spain," said Carlos Mulas, 56, of Madrid, before boarding a tour bus. "But Washington is so beautiful. We expect to enjoy it."

Several members of tourist Gregg Selewski's extended family spent their nights in a recreational vehicle parked at a campground in Greenbelt, Md. They vowed to see everything, despite the heat.

"This is what we came to do," said Selewski, 13, of Canton, Mich.