Smoke from the fires has wafted through northeast U.S. states for weeks now, but it's only recently been noticeable in most places.
New York Gov. Kathy Hochul said Tuesday's hazy skies "were hard to miss," and New York City Mayor Eric Adams encouraged residents to limit outdoor activities "to the absolute necessities."
WHAT'S HAPPENING?
Smoke from Canada's wildfires has been moving into the United States since last month. have been burning for at least several days.
The U.S. Environmental Protection Agency said hazy skies, reduced visibility and the odor of burning wood are likely, and that the smoke will linger for a few days in northern states.
"It's not unusual for us to get fire smoke in our area. It's very typical in terms of northwest Canada," said Darren Austin, a meteorologist and senior air quality specialist with the Rhode Island Department of Environmental Management. But, usually, the smoke has been aloft and hasn't affected people's health, he said.
The Quebec-area fires are big and relatively close, about 500 to 600 miles (roughly 800 to 970 kilometers) away from Rhode Island. And they which resulted in a short-lived air quality alert on May 30, Austin said.
Jay Engle, a National Weather Service meteorologist based in Upton, Long Island, said the wind trajectory that allowed smoke and hazy conditions to be seen in the New York City area could continue for the next few days. Of course, he said, the main driver of conditions is the fires themselves. If they diminish, the haze would too.
WHAT'S THE BIGGEST CONCERN?
Air quality alerts are triggered by a number of factors, including the detection of fine-particle pollution — known as "PM 2.5" — which can irritate the lungs.
"We have defenses in our upper airway to trap larger particles and prevent them from getting down into the lungs. These are sort of the right size to get past those defenses," said Dr. David Hill, a pulmonologist in Waterbury, Connecticut, and a member of the American Lung Association's National Board of Directors. "When those particles get down into the respiratory space, they cause the body to have an inflammatory reaction to them."
Trent Ford, the state climatologist in Illinois, said the atmospheric conditions in the upper Midwest creating dry, warm weather made it possible for small particulates to travel hundreds of miles from the Canadian wildfires and linger for days.
"It's a good example of how complex the climate system is but also how connected it is," Ford said.