The mercury reached 92 degrees in Boston shortly after noon Thursday, breaking the old record of 91 degrees for May 18 set in 1936, according to the National Weather Service.
The 81-year-old record for the day of 90 degrees also fell in New York City, where it was still 91 degrees in Central Park shortly before 4 p.m.
It was the second straight day of midsummer-like conditions in the Northeast, though forecasters said a cooling trend would move in Friday and return the region to more seasonable conditions.
The warmth came just days after much of the region endured a cold, rainy Mother's Day Weekend.
Heat-starved locals in Jamestown, Rhode Island, took advantage of the warm weather Thursday to eat lunch at restaurants with outdoor patios.
Mary Ann Williamson and Peggy Schreiner went out to eat to celebrate Williamson's recent retirement. Schreiner said the weather was 'spectacular.' Not minding the heat, they chatted to extend their time outside.
'As long as it's not a rainy summer, I'll be happy. I was worried about that,' Williamson said.
Other places where records fell included Hartford, Connecticut, where temperatures reached 94 degrees, and in Providence, Rhode Island, where it hit 93.
In Maine, where records also fell throughout the state, the Department of Environmental Protection issued an air-quality alert through 11 p.m. Thursday.
In Boston, the National Park Service said on Twitter that the Bunker Hill Monument, a major Revolutionary War tourist attraction, was closed to visitors for a time because of the heat.
Far from unheard of
Alan Dunham, a meteorologist at the Massachusetts office of the weather service, said 90-plus degree heat in mid-May was unusual in the Northeast, but far from unheard of.
And because dew points were low, Dunham said the heat did not feel nearly as oppressive as it might when humidity levels are much higher in July or August.
'As they say out west, it's a dry heat,' he said.
Matt McKenna, from Holliston, Massachusetts, was taking a break from work at the Boston Harbor Hotel. As he sat on a bench at Rowe's Wharf, he wondered what happened to spring.
'It seems like we just skipped over it, went straight into summer,' said McKenna, who admitted to not being a huge fan of hot weather.
'I like the cold, I'm a snow guy,' he said.
Sipping on an ice coffee near the city's financial district, Jenna Gagne, of Hull, Massachusetts, wondered if the weather swings were related to climate change.
'I feel like its jut so inconsistent, that it has to be something related to (global warming),' Gagne said. 'I just feel like it's changing a lot.'
Her friend, Lisa Hart, was more skeptical.
'I think it's just New England,' she said, referring to the region's notoriously fickle weather.
Seeking out snow
Indeed, some die-hard skiers were still trying to traverse New England's northernmost peaks as late as this week.
As they relaxed in their boat in Westmore, Vermont, Kurt and Alison Harrison recalled that about a year ago when they vacationed in the same spot, it was snowing. On Thursday, temperatures hovered near 90.
'There's no humidity up here ... it's so nice,' Alison Harrison said.
Despite temperatures in the 90s in Concord, New Hampshire, thousands of people took to the streets Thursday evening for the Merrimack County Savings Bank Rock `N Race. Organizers doubled up on the water along the 3.1 mile course and had an extra ambulance on hand as well additional medical staff.
'You could feel your face flushing,' said Michael Bacotti, 38, of Londonderry, who completed the race with his 5-year-old and 6-year-old sons. 'It was hot like an oven.'