Smoke from wildfires in provinces of Ontario and Quebec in Canada made Philadelphia’s iconic Belmont Plateau skyline nearly invisible on June 7, 2023. (Kimberly Paynter/WHYY)

If you had plans to enjoy the early June weather and long evenings in Philadelphia this week, maybe think again. Health officials on Tuesday evening issued a warning to avoid going outdoors as much as possible.

Smoke is being funneled down from raging wildfires in Quebec due to “a unique weather pattern,” the Philadelphia Health Department said. It’s created a noticeable haze around the region which is dangerous because it’s made up of tiny particles that can go deep into your lungs when inhaled. 

Philly’s air quality index on Wednesday morning was extremely high: with meters registering an AQI of 212, above red and into the purple range. For reference, 0 to 50 is considered “good” and anything above 200 is “very unhealthy. (You can check your area and stay up to date at

What should you do about this? Here are some recommendations from the Health Department:

  • First, try to avoid going outside
  • If you have to go outside, wear a mask (they come in handy!)
  • Skip going for a run — heavy breathing just makes you inhale more of the particulate matter
  • Try to avoid busy areas where air flow is weak and pollution is high (i.e. it’s probably better to be in a park than in the middle of the city)

All this is worse for people in sensitive groups, which include children and elderly people, pregnant people, and anyone with an existing respiratory or heart condition. Check on your friends and neighbors!

Other cities along the northeast corridor are also experiencing the haze, including New York and D.C. It’s also affecting other parts of Pennsylvania. The state Dept. of Environmental Protection issued an “Air Quality Action Day” alert for Wednesday that covers Philly, the Lehigh Valley, the Susquehanna Valley, and Pittsburgh.

The problem is caused by high levels of particulate matter known as PM 2.5 — less than 2.5 microns in diameter, about thirty times thinner than a human hair, according to Philly health officials.

Additional pollution just makes the problem worse, so the city is asking people to try to reduce their personal contribution. How? 

  • Skip any unnecessary car trips (carpool whenever possible)
  • Don’t let the car idle if you do drive
  • If you happen to have a lawn and a gas-powered mower, put off using it to another day

How long will this last? Probably another couple of days, according to the Pa. Dept. of Environmental Protection. 

“The area of low pressure will finally begin to be pushed eastward on Friday,” per Daniel Roble, a DEP air quality program specialist. “This may not end the threat for periods of elevated concentrations due to the smoke for Friday but may at least begin a transition to an improvement in air quality conditions for the weekend.”

If it rains, Roble said — and this has been one of the driest periods in Philly history, so who knows if it will — that would also help clear the smoke.