Hundreds of Canadian wildfires trigger US air quality alerts as toxic haze spreads

Canadian wildfires has crossed into the United States triggering emergency air quality alerts in over 20 states.

As reported more than 850 wildfires spread massive plume of toxic particulate matter in the atmosphere.

Prevailing northwesterly winds have funneled the dense, gray-and-yellow haze south into highly populated U.S. corridors, severely impacting major metropolitan areas.

The rapidly deteriorating conditions are driven by severe, ongoing drought and record-breaking summer heat, with major fires raging across Ontario, Quebec, Alberta, and Saskatchewan and other regions.

The air quality in large parts of the northern states of Michigan and Minnesota is deemed "hazardous" by the US Air Quality Index program, with people recommended to stay indoors.

Alerts span the Upper Midwest, the Great Lakes region and into the northeast, the US national weather service (NOAA) said in an update on Thursday.

In Canada, one fire in northern Ontario forced residents from local First Nations to evacuate, with one chief saying that her community has been "burnt to ashes"

There are currently 858 fires actively burning in Canada, including 30 new fires on Thursday, according to the Canadian Wildland Fire Information System. The vast majority are burning out of control.

The large cluster of fires affecting northwestern areas of Ontario are responsible for sending thick plumes of smoke and poor air quality across Thunder Bay and Toronto, with lower concentrations of smoke high in the atmosphere drifting over the Great Lakes and above New York with hazy skies and redder sunrise and sunsets likely.

Current situation across regions is intensifying.

Newyork:

In western regions of New York state, the air quality on Thursday is considered "very unhealthy", while in the New York City metro area the air quality is "unhealthy".

New York has extended its heat emergency plans and activated its air quality emergency protocols - with hundreds of cooling centers and KN95 masks being made available citywide.

Ontario:

In Ontario, there will be quite widespread thunderstorms over the next few days, but the rain may not be enough to make much of a difference.

New Jersey:

Northwesterly winds will continue to blow the smoke into northern US states for the rest of this week and into the weekend, leading to concerns smoke will drift into New Jersey where Sunday's World Cup final is due to take place.

Quebec:

A change in the wind direction by Monday means that the smoke will tend to be steered across Quebec with an improvement in air quality further south in the US.

Other regions:

Air quality in the Midwestern city of Detroit is currently the worst in the world, Swiss air quality tracker IQAir said, followed by Minneapolis, Chicago and Toronto.

Republican lawmakers in the state of Michigan have penned an open letter to Canadian Prime Minister Mark Carney asking for better management of the country's wildfires, expressing frustration for a third year in a row.

"A year has passed, the season has come around again, and nothing has changed except that our patience has run out," said the letter, signed by four state House representatives .

Pete Hoekstra, the US ambassador to Canada, struck a more diplomatic tone in a statement on Wednesday commending wildfire fighting efforts from both countries.

Wildfires are a part of the natural life cycle of Canada's vast boreal forest, but they have become more frequent since 2015, said Laura Chasmer, a professor of geography and the environment at the University of Western Ontario.

"This is associated with some of the extreme climate warming that we've been seeing, and the atmospheric drying of the surface," she said.