Have you noticed a smoky haze across the skies above Philadelphia this week?
That's because, once again, smoke from wildfires in and the western United States and Canada has drifted over the city, causing a hazy sky.
Why is the wildfire smoke over the Philadelphia region?
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A high pressure system over the area has been bringing dry air that is centered just to the northwest of Philadelphia, resulting in a northerly airflow that is delivering the smoke from a wildfire in Canada.
The most active wildfires are in the Northwestern U.S. and Western Canada.
The smoke is being carried over Canada and then dropping back down into the Philadelphia area due to the high pressure.
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The thicker smoke is surrounding the region, but isn't not directly over Philly, so conditions aren't too bad.
Smoky haze to ease Friday
We’re experiencing another smoky morning Friday, like Thursday.
The morning smoke will ease as high pressure moves past our area and offshore, pushing the smoke to the east.
While the smoke is mostly passing overhead, it can still be seen as a hazy sky, especially at sunrise and sunset the past few days. While it’s smoky now, you’ll notice less smoke Friday afternoon and during sunset.
Last year, poor air conditions in the region were also caused by Canadian wildfire smoke.
What happens this weekend?
As the high pressure moves offshore, we’ll also see an increase in humidity, which will be more noticeable later Friday and especially this weekend.
This shift will also bring a chance of showers and thunderstorms, as a slow-moving cold front moves toward us this weekend. There will be a continued chance of storms into Monday.
We can expect things to clear out starting next Tuesday.
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