Smoke From Canada’s Wildfires Worsens Air Quality in Northern U.S.

Hundreds of wildfires continued to blaze on Tuesday across Canada, exacerbating an already active wildfire season that was only expected to worsen, and sending smoke into portions of the United States, creating poor air quality levels.

In Ontario, a layer of haze blanketed parts of Ottawa and Toronto, where Canadian officials warned residents about the poor air quality, as smoke moved in to portions of northern New York State and Vermont. All of New York City was under air quality alert on Tuesday because of the smoke; by the afternoon, the Manhattan skyline was obscured by hazy skies.

There were more than 400 active wildfires in Canada on Tuesday, according to the Canadian Interagency Forest Fire Centre, with more than 200 deemed to be “out of control.”

In eastern Canada, Quebec was most affected by wildfires as of early afternoon on Tuesday, with more than 150 active blazes across the area, according to the fire agency. Residents in some areas were being encouraged to shut their windows and doors, local officials in Quebec said.

Videos and images showed some fires blazing for miles, sending dark smoke plumes billowing into the sky.

At a news conference on Monday, Prime Minister Justin Trudeau said he was in contact with local officials across Canada about the fires.

“This is a scary time for a lot of people,” Mr. Trudeau said.

As of Monday, an estimated 26,000 people across Canada had been evacuated from their homes because of wildfires, Bill Blair, Canada’s minister of public safety, said at the news conference.

“The images that we have seen so far this season are some of the most severe ever witnessed in Canada,” Mr. Blair said.

Many Canadians who have had to evacuate in recent days had just a few hours to pack before fleeing their homes, Mr. Trudeau said.

“When people lose their homes, they don’t just lose a roof and their possessions,” Mr. Trudeau said. “They lose a special place where they saw their children grow up, where they built a life for themselves. This is incredibly difficult and heartbreaking.”

Bands of smoke from the numerous wildfires were expected to shift southward across the border on Tuesday, creating hazy skies and prompting the U.S. National Weather Service to issue air quality alerts for parts of the upper Great Lakes and the Northeast.

Large swaths of Minnesota were under air quality alerts through the evening on Tuesday, the Weather Service said. Light winds were expected to push smoke from wildfires in Quebec across Minnesota. Smoke was also predicted to move into the state off Lake Superior.

Weather officials warned that people more sensitive to poor air quality, such as people with lung disease and heart disease, children and older adults, should limit certain activities outdoors.

Farther east, air quality alerts were also in place for multiple counties in upstate New York and New York City through midnight. Similar alerts were issued for parts of Connecticut, Massachusetts and Vermont.

Satellite images of North America on Tuesday showed light brown smoke streaming south from the fires. The smoke appeared to be particularly thick over portions of Quebec, Ontario and New York. Hazy conditions could also reach as far south as the Carolinas.

John Cristantello, a meteorologist with the Weather Service in New York, said that a thick area of smoke over Lake Ontario was expected to move toward the New York City area by late afternoon or early evening on Tuesday.

“It will probably linger around through much of the night,” Mr. Cristantello said.

In addition to the poor air quality levels, smoke from the wildfires could a create vivid, reddish sunset, similar to what New York saw last month when smoke from Canadian wildfires had drifted south.

Such sunsets and poor air quality levels could persist this summer if Canada continues to see many wildfires, Mr. Cristantello said.

In Canada, Mr. Blair said that hundreds of soldiers had been deployed across the country to help with firefighting efforts. Other government agencies were on standby if wildfires damaged critical infrastructure, Mr. Blair said.

Mr. Trudeau said on Monday that forecasts indicated that “this may be an especially severe wildfire season throughout the summer.”

To date, there had already been more than 2,200 wildfires in Canada this year, according to the country’s fire agency.