When Will Smoke Clear In PA? What To Expect

PENNSYLVANIA — Air quality levels are very unhealthy in parts of Pennsylvania as a plume of smoke from wildfires in Canada pushes south. Though Thursday will allow some people to breathe easier, certain groups sensitive to the air pollution will still be uncomfortable outside.

Additional smoke from the raging wildfires in Canada will reach Pennsylvania on Wednesday afternoon, said forecasters, and will stay through at least Thursday.

"Even thicker smoke and resulting poor air quality ('very unhealthy' levels on the air quality index) is quickly pushing southward and will expand across the rest of our area this afternoon & evening," said the National Weather Service in Mount Holly on Wednesday afternoon.

Air quality conditions in Allentown, Scranton, and several other communities in the north and east were considered "hazardous" as of Wednesday afternoon according to AirNow.gov, which monitors the air quality index. Communities closer to Philadelphia were measuring "very unhealthy" levels of particulate matter and ozone as of 4 p.m.

The Keystone State may not see the conditions clear completely until Friday or Saturday, said the National Weather Service.

State environmental officials issued a "Code Red Air Quality Action Day" across Pennsylvania through Wednesday night.

Smoke and particulate matter in the air are making unsafe conditions for some groups of people like children, the elderly, and people with asthma.

Even for those who do not have respiratory conditions, exercising too much or spending too long outside can irritate the throat, eyes, and lungs.

"Pennsylvania residents should limit their outdoor activities, especially older people, children, those who are active outdoors, and those with lung or respiratory conditions such as asthma, emphysema, or bronchitis," said the Department of Environmental Protection.

The poor air quality has already forced the cancellation of several outdoor events Wednesday, including Major League Baseball games in both New York City and Philadelphia.

Thursday's Air Quality Index (AQI) levels are expected to be slightly better, but still unhealthy for people with heart or lung disease, older adults, children, and teens.

The National Weather Service in Mount Holly noted that Pennsylvania residents "may not see substantial relief until Friday into Saturday."

Showers are possible in some parts of the state Thursday and Friday.

Related articles:

• Code Red Issued: How To Stay Safe In PA’s Wildfire Haze
• Wildfire Smoke Will Linger In PA: What To Expect

Here is the forecast in southeast Pennsylvania through Friday from the National Weather Service:

Wednesday night

Widespread haze. Widespread smoke, mainly before 2am. Partly cloudy, with a low around 50. Northwest wind 5 to 10 mph.

Thursday
A slight chance of showers between 2pm and 5pm, then a slight chance of showers and thunderstorms after 5pm. Widespread haze. Areas of smoke before 8am. Sunny, with a high near 76. West wind 5 to 10 mph. Chance of precipitation is 20 percent.

Thursday night
Partly cloudy, with a low around 52. North wind around 5 mph.

Friday
A slight chance of showers, then showers likely and possibly a thunderstorm after 2pm. Partly sunny, with a high near 73. Northwest wind around 5 mph. Chance of precipitation is 70 percent. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Friday night
Showers likely and possibly a thunderstorm before 8pm, then a slight chance of showers between 8pm and 2am. Partly cloudy, with a low around 51. Northwest wind around 5 mph. Chance of precipitation is 60 percent. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.