An air quality health advisory has been issued for New York City and the surrounding area Wednesday amid a stretch of hot, humid weather that will keep the tri-state sweating for much of the rest of the week.
The advisory from the New York Department of Environmental Conservation (DEC) went into effect at 11 a.m. Wednesday and stretches through 11 p.m. for the NYC metro area and Long Island. There are also alerts in place for Rockland and Westchester counties, parts of New Jersey and coastal Connecticut. The pollutant of highest concern is ozone, the DEC said in a release.
The department said health advisories are issued when levels of fine particulate matter (PM2.5) are expected to exceed an Air Quality Index (AQI) value of 100 — a level at which those with health conditions like asthma could have difficulty breathing. Young children and those with respiratory diseases should consider limiting outdoor physical activity when levels of ozone are peaking, generally in the afternoon into the early evening. That also is true for those who work or exercise outside.
Why are ozone levels higher than normal? The DEC said the increased heat leads to the formation of ground-level ozone, which is a big component of photochemical smog. It is generally a result of automobile exhaust and emission sources from outside the state, according to the DEC, and has nothing to do with the protective ozone in the Earth's upper atmosphere.
The heat the city and the rest of the tri-state is feeling will continue for the next few days, with temperatures nearing or topping 90 both Wednesday and Thursday. It won't technically be a heat wave for NYC (Tuesday peaked at 89 degrees) but it will likely be the case for other places, like Newark. Either way, it's going to be a stretch of hot, humid weather, and it will feel gross outside.
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The air quality alert in place does not extend into Thursday, at least that was the case as of Wednesday evening. Storm Team 4 says on top of hot temps, isolated showers and storms could pop up Thursday. Stronger storms might surface overnight and into Friday. As for the weekend, Saturday looks to be the drier half of the weekend.
Wednesday's advisory comes less than a week after the city's latest air quality advisory that was issued in the days after the Fourth of July. Part of last week's advisories were due to hotter temperatures as well as elevated levels of fine particulate matter (PM2.5) pollution that stemmed from the remnants of fireworks.
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Ground-level ozone isn't as visible as PM2.5 because it is a colorless gas, the DEC said, though it can produce hazy skies and reduced visibility if concentrations are high enough.
If the terms fine particulate matter or PM2.5 ring a bell, it's the same unit of measure used when smoke from the Canadian wildfires blanketed with city. Last week's elevated levels were not related to those wildfires whatsoever, according to the DEC, nor is Wednesday's air quality advisory.
It also comes as the New York City Council was set to hold hold a hearing Wednesday on Mayor Eric Adams' response to the smoky air that blanketed the city in June. A report from the public advocate's office accused the city's response of being too slow — saying the Adams administration should have been better prepared.
A spokesperson for Adams said public messaging about potentially bad air quality began a week before the worst of the smoke.
"Based on the forecast, we did everything we should have done,” said Zach Iscol, the commissioner of the Office of Emergency Management, after being questioned by Oversight Committee Chair Gale Brewer. He added: "I think the city did the right thing."
Public Advocate Jumaane Williams grilled Iscol at the hearing, leading to a robust back and forth in which Williams asked why more wasn’t done to inform the public. Iscol stuck to his view the city did what it could with the info available.
See below Storm Team 4's exclusive 10-day forecast.
