Wildfire smoke tracker: Where the air pollution is headed next

The northeast of the United States is battling smoke from 400 wildfires raging across Canada which have burned more than 6 million acres and led to mass evacuations.

And it’s far from over: Canadian officials warned that this could be the country’s worst wildfire season on record.

Smoke has darkened skies and made it difficult to breathe in at least half a dozen states and large parts of Canada, including major cities like New York, Toronto, Ottawa, Washington DC and Philadelphia.

Live: New York’s Central Park clouded in haze from Canadian wildfires

New York was ranked number one for the worst air quality in the world at 2pm local time on Wednesday with the Air Quality Index (AQI) at 342 – with the air pollution level described as “hazardous”.

In a sign of how extreme conditions are New Delhi was in second place with an AQI of 190. Toronto is in fourth place with AQI 160.

In areas with high levels of air pollution, public health officials were advising people to limit their time outdoors and wear masks. Vulnerable populations including children, the elderly, and those with underlying conditions like asthma and heart disease, should particularly heed the warnings.

Which states and cities are affected by smoke?

At least eight US states have air quality alerts issued in places, impacting an estimated 60 million people.

Among the worst-affected locations were major cities like New York, Washington DC, Philadelphia, Detroit, Jersey City, and New Haven.New York City was ranked number one for the worst air quality in the world at 2pm local time on Wednesday with the Air Quality Index (AQI) at 342 – the air pollution level described as “hazardous”, according to global monitor IQAir.

Which direction is the smoke moving?

More thick smoke is pushing south from Canada through Pennsylvania and New Jersey and is expected to blanket New York City around 4pm local time in time for the evening commute.

People were being warned to take extra precautions due to less visibility, a drop in air quality and the “campfire”-like smell.

The fires have been burning for weeks. Why is it smoky now?

The fires in Quebec province started this weekend and blazes in Nova Scotia, on the Atlantic Coast, began last month.

A storm system off Canada’s east coast is pushing the smoke south over the United States.

This weather pattern is expected to continue until at least the weekend.

This article is being updated