The smoke from the Canadian wildfires is producing unhealthy air quality across the state.
Some school activities were suspended or postponed because of it.
The worst of the smoke and air quality was in New Haven and Fairfield counties where levels reached the "hazardous" category.
The Connecticut Interscholastic Athletic Conference has postponed the state lacrosse and tennis tournament games for this afternoon because of the air quality due to smoke from wildfires in Canada.
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Plymouth schools rescheduled the Fisher Elementary field day due to the air quality and they'll be reevaluating the air quality conditions Thursday to see if they need to do the same for Plymouth Center.
Norwalk Public Schools suspended all outdoor activities Wednesday, including school trips, due to the impact of the unhealthy air quality.
Fairfield Public Schools moved all “unnecessary outdoor activities” indoors, not including previously scheduled field trips or athletic practices.
When the smoke gets really thick, anyone can experience symptoms that include a headache, fatigue, nausea, shortness of breath or even a slight cough.
Doctors say these symptoms should dissipate over time, but for people with pre-existing conditions, the smoke will have lingering affects on their health.
The smoke contains microscopic pieces of ash. It's a fraction of the diameter of a human hair. With every breath you take, you inhale them and they can settle deep into the lungs, causing irritation and flareups of existing illnesses.
Smoke from Canada's wildfires has been moving into the United States since last month. The most recent fires near Quebec 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 away from Rhode Island. And they followed wildfires in Nova Scotia, 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.
As the smoke blankets the northeast and midwest, some say it's a glaring reminder of a worldwide issue.
“Whether it’s wildfires, swings in temperature, smog, all of these things contribute to respiratory health," said Yale New Haven Hospital Pulmonary and Critical Care Dr. Geoff Chupp.
“I mean, I think it’s important to recognize the global impact of climate change and that these wildfires don’t affect people locally, it affects people on an international scale," said Olivia Dumont, of New Haven.
Doctors say if you use medication like a rescue inhaler, you should take it about 20 minutes before going outside for a walk. While these conditions persist, you can keep your doors and windows closed at home to keep the smoke out.