Wildfire smoke blankets New York 0:44

(CNN) -- A thick plume of smoke traveling south from Canada on Wednesday tore through the Northeast and Mid-Atlantic, affecting some of the most densely populated regions of the U.S., including the New York City metropolitan area.

The smoke sparked widespread concern among health professionals, forced the suspension of flights at a major New York airport and led to the cancellation of outdoor school activities.

And now forecasts say he could stay for days.

(Credit: Eduardo Munoz Alvarez/Getty Images)

The smoke, which originates from more than 100 active fires in central Quebec, descends from the back of a low-pressure system in New England.

Wednesday's thickest smoke spread from Lake Ontario to Long Island and moved slowly south. It will persist in the New York City metropolitan area and much of New Jersey into Wednesday night and into the early morning.


  • Philadelphia is under "code red" alert as millions from East Coast to Canada suffer from unhealthy air from Quebec wildfires

But winds will also start pushing that thick band of smoke farther south into the Mid-Atlantic, so it could soon reach cities like Washington and Baltimore.

On Thursday morning, Delaware, Maryland, northern Virginia and the nation's capital could have worse air quality due to the same smoke that hit New York City on Wednesday.

While Thursday may see an improvement for many in the New York area, there is still likely to be a lot of smoke and air quality could be reaching unhealthy levels once again.

Unfortunately for those in the Northeast, the weather won't help. The low pressure that is funneling smoke into the U.S. is forecast to remain over New England over the weekend, meaning northwesterly winds will continue to carry Canadian smoke eastward from the Great Lakes and northeastern U.S. over the next few days.

This pattern could eventually break next week as a new storm system approaches from the west. Significant rainfall and stronger winds is exactly what the Northeast needs to clear the smoke.

A smoky summer

Unfortunately, the next few months could raise the prospect of a summer of smoke for Canada and the U.S., with most of Canada's fire season — which usually doesn't end until September — still to come.

A hot, dry spring has sparked an incredibly active start to the fire season across most of Canada, and massive fires in Alberta and Saskatchewan began affecting air quality in the U.S. and Canada in May.

Last week, wildfires in Nova Scotia pushed smoke south. Over the weekend, the fires moved to Quebec. For all these places, the hottest part of the year is yet to come and the peak of the fire season doesn't come until late July.

Wildfires have already burned a full year's worth of acreage in Canada so far this year. In a typical year, only 10 to 15% of the annual average would have burned by the first week of June.

Without a significant pattern of cold and humidity in Canada, these fires are likely to continue to burn and new ones emerge over the next few weeks.

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