One couple in Washington D.C. said, "It's like being in Georgia. It's awful."
New York's heat index cranked up to 105.
Weathermen from Hartford to New York to Philadelphia are cranking up their mega Dopplers and ramping up their forecasts.
"What we have here is the sweat factor," said one forecaster.
The flash heat wave has sent more people to emergency rooms than expected for this time of year.
"People with heat exhaustion can have symptoms like muscle aches, muscle cramps, dizziness, extreme fatigue, things that almost seem like they have a viral illness," said Dr. Gabriel Wilson of St. Luke's/Roosevelt Hospital.
"And you're seeing this already?" asked Brzezinski.
"Yes," Wilson said.
"And it's not even summer."
"I know. We're in for a long one."
The elderly are most vulnerable, as are young children.
"It's so hot you don't even want to talk," said one child.
So schools that haven't yet closed for summer are enforcing summer hours -- many operating on half-day schedules or closing altogether.
"We realize its very warm for our kids and so what we've done is a modified schedule -- half day," said a Philadelphia educator.
Meteorologists say this steamy June is just the flip side of a gloomy May. Last month, the bulging jet stream from Canada brought rain and chill to the Northeast. Now a large mass of tropical heat is pushing in from the Mississippi Valley, and this pattern, experts say, makes for a sweltering August.
"You think it's bad now -- look out in two more months!" one meteorologist said.
But 81-year-old Ginger Nestler says it's all in what you wear.
"I'm dressed in light colors, all cotton, cotton, so it's very cool and very porous, and loose fitting."
There were heat advisories up and down the eastern seaboard. Even in the shade it's extremely uncomfortable. The heat wave could last another day as it's expected to break on Thursday.