Over 100 million in eastern US warned of 'unhealthy' air as Canadian wildfire smoke spreads south, west

NEW YORK - Choking smoke from wildfires burning in Canada continues to billow into the eastern U.S., where more than 100 million Americans across the Northeast and into the mid-Atlantic will again experience "unhealthy" to even "hazardous" air quality levels.

New York City air quality levels reached the worst in recorded history Wednesday afternoon when the Air Quality Index (AQI) hit 405, smashing the previous record of 279 back in July 1981.

The wildfire smoke isn’t only causing issues on the ground. Flights from across the region have also been affected because visibility remains low.

On Thursday morning, the FAA said in a tweet that it has paused flights from the Northeast, mid-Atlantic Ohio bound for New York’s LaGuardia Airport. A ground stop was also put into effect at Philadelphia International Airport due to smoky conditions on Thursday morning.

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Where is the smoke from the Canadian wildfires?

Impacts from the Canadian wildfire smoke are expected to stick around for the next few days. 

For Thursday, an area of low pressure swirling off the Northeast coast will drift a little to the west, shifting the worst of the smoke to the south and west.

While major cities such as New York City experienced hazardous air quality on Wednesday, metropolitan areas such as Philadelphia, Baltimore, and Washington will see smoke conditions deteriorate during the day on Thursday.

Even though the smoke has been around for weeks along the U.S.-Canadian border, weather patterns left most of the particles confined to higher altitudes, keeping impacts well above ground level.

But the recent development of a northerly wind over the fires, combined with high pressure helping to trap the smoke and pollutants closer to the surface, brought smoke to the surface over heavily populated areas of the Northeast. And the FOX Forecast Center believes that pattern could last through the rest of the workweek.

By Friday morning, the worst of the smoke will push off Long Island and into the Atlantic Ocean. However, Washington D.C. and Baltimore could still be dealing with very smoky conditions.

Areas farther to the west will also be experiencing unhealthy air quality levels as more smoke arrives. In Pennsylvania, cities from State College to Pittsburgh across the western half of the Keystone State will need to take proper precautions and limit time outdoors due to the potentially hazardous AQIs.

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Where are Air Quality Alerts in effect on Thursday?

More than 100 million Americans across the eastern half of the country will be under Air Quality Alerts on Thursday.

In the Northeast, cities from Providence, Rhode Island to Hartford, Connecticut, New York City and Philadelphia are included in those Air Quality Alerts.

In the mid-Atlantic, cities such as Baltimore, Washington D.C. are included. In addition, the entire state of North Carolina and areas of northeastern South Carolina are experiencing Air Quality Alerts.

NEW YORK, PHILLY, WASHINGTON SMOTHERED IN ‘UNHEALTHY’ AIR AS CANADIAN WILDFIRE SMOKE POURS INTO NORTHEAST

What are the current air quality levels in the Northeast?

Air quality levels have improved across northern New England. However, "moderate" to "Unhealthy" conditions are continuing across southern New England and across the Northeast.

"Very Unhealthy" to "Hazardous" air quality levels are in southern New Jersey and eastern Pennsylvania. Philadelphia was experiencing "Hazardous" air quality levels Thursday morning.

By Thursday morning, Washington D.C. air quality levels reached "hazardous" levels when it hit an AQI of 313.

What cities are experiencing the worst air quality levels in the U.S.?

Cities in the Northeast and mid-Atlantic are currently experiencing the worst air quality levels in the country.

Those cities are mostly located in Pennsylvania, Delaware and in Washington.

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