Outdoor enthusiasts weren't driven inside despite record-high temperatures and heat indexes surpassing 100 degrees in several areas across the nation's midsection and beyond.

Campers turned out at a KOA campground east of Kansas City, though Jeraldine Bush, who works on the grounds, said people that had air conditioners were running them.

In Nashville, Tenn., going outside felt "like walking into a fire," said Tabatha Collins, general manager of Two Rivers Campground. She said the campground was "pretty full" and people were spending lots of time in the swimming pool.

About 16 miles southeast of Madison, Wis., where weather.com predicted a heat index near 105 degrees Friday, it was "very warm and muggy," said Bert Davis, owner and manager of Badgerland Campground. For campers that made reservations, "they're not letting the heat ruin their vacations," he said, though he noted a dip in the number of drop-in campers.

But not all campers were braving the heat. At Bass' River Resort, about 100 miles southwest of St. Louis — which saw its ninth straight day above 100 degrees — manager Stephan Bass is seeing people move from tents to air-conditioned cabins.

Forty-five miles north of Chicago — which saw its third consecutive day in triple digits — attendance hasn't really changed at Six Flags Great America, said park spokesman Brandon Bruce. But there are more people choosing to go on the water rides: "People are definitely taking advantage of that, trying to stay cool," he explained.

It may be a holiday week, but the heat is not taking a vacation anytime soon. The record-breaking temperatures in the Midwest are expected to spread to the East Coast over the weekend — a region still experiencing power outages from last weekend's storms.

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