Those outdoors in New York City on Wednesday couldn't help but take notice of the strong campfire smell and eerily orange skies.
"It's kind of scary out here, like the apocalypse is about to happen. And it's hard to breathe," Michelle Karwejna told ABC New York station WABC. "It feels like I'm at a campfire that I don't want to be at and there's no s'mores."
Plumes of smoke from ongoing wildfires in Canada have prompted serious air quality alerts in at least 16 states. Hazy skies, low visibility and poor air quality will be present in most of the Northeast and the Midwest and even as far south as the Carolinas.
New York City is experiencing the worst air quality since the 1960s due to the wildfires, officials said. The Air Quality Index hit 484 on a scale of 500 Wednesday evening; anything above 300 is considered hazardous.
New York City Mayor Eric Adams called it an "unprecedented event" during a press briefing on Wednesday while urging New Yorkers to avoid going outside if they can.
"Very, very scary. Just walking down the street and feeling like I'm going to have an asthma attack. That's how bad the air quality is," Jordan McKenzie, a Brooklyn resident who has asthma, told WABC Wednesday.
In Baltimore, Tea Williams, who also has asthma, put on a mask due to the smoky conditions in the city.
"When I walked outside this morning, you could tell it was foggy and it smelled like something was burning, it smelled like a fire," Williams told Baltimore ABC affiliate WMAR on Wednesday.
Francisco River, who was undeterred by the conditions and was out rollerblading, told WMAR "it smelled like a tire was burning."
The smoky conditions are expected to impact the region through the end of the week, experts said.
The smell of smoke caught some off guard before they learned the cause.
"I woke up this morning and went outside, and it was very strange," Molly Hickey told Rochester ABC affiliate WHAM on Tuesday. "I actually checked the weather to see if it was about to rain, and then it smelled like our neighbors might be having a campfire and just sort of an eerie feeling."
In Buffalo, New York, Megan Luongo told Buffalo ABC affiliate WKBW that when she went for a walk on her lunch break on Tuesday, she "smelled the fire."
"I wasn't sure what it was totally, but now I know," she told the station.
"I'd definitely be concerned that it's been here for days now and it's not going away," Luongo told WKBW.
The conditions in Scranton, Pennsylvania, were "brutal" on Wednesday, prompting garbage and recycling pickup to be put on hold, Scott Pietreface, the director of the city's Department of Public Works, told Scranton ABC affiliate WNEP.
"This is the first time we've seen this," he told the station.
Nikki Sanders said she wore a mask as she walked home from work in Scranton on Wednesday.
"The smoke is strong, and I didn't want to breathe too much of it in," Sanders told WNEP. "I wanted to try and protect myself as much as I can."