That means hundreds of cooling centers across the five boroughs are now open, cooling vans are hitting the streets, the FDNY is handing out spray caps for fire hydrants and pool hours are extended until 8:30 p.m.
On an uptown No. 1 train, Eyewitness News found riders suffering in the sweltering heat with no air conditioning. The MTA claims that 99% of their trains have functioning climate control.
But on Wednesday morning, we found the 1%.
Alfonso Carrillo takes the train to work every day and he knows what it's like.
"You're not supposed to switch cars while it's moving, but it's just like I rather move away from the heat," Carrillo said. "I don't want to pass out or nothing, you know? It's just like that. That's how hot it is, you know? It's like in a tin can. It's just like it's the worst feeling."
With temperatures expected to soar and air quality plunging from the Canadian wildfires, New Yorkers are being urged to take extra precautions.
Tips to stay cool as dangerous heat hits NYC
"We do have air quality concerns, we're at the unhealthy stage for sensitive groups, right? People with asthma or other very young, older New Yorkers," said NYC Emergency Management Commissioner Christina Farrell. "But we could, as the week goes on, get into some higher levels where it will affect everyone."
In the last heat wave, five New Yorkers did not survive the searing heat. And people are urged to limit outdoor activities and to stay hydrated.
We found Lori-Jill Seltzer waiting for a downtown bus-and hoping it's air conditioned.
"I really hope it has air conditioning, I moved from California a few months ago, had the worst winter that they've had in what 30 years, and now like the hottest summer, so you know, I escaped the fires, but here I am," Seltzer said. "Yeah, it's like kind of brutal."
Experts say to limit your time outdoors if you can and stay hydrated.
WATCH | Krista McNally has more on how road crews are taking precautions outside:
Road crews take precautions during heat wave in Suffolk County
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