Tuesday’s Forecast: High pressure will allow for another day of mostly sunny skies across the region. Winds will be light, limiting mixing for the day. A plume of smoke moving overhead from wildfires across Canada will cause concentrations of fine particulate matter (PM-2.5) to rise to levels in the code ORANGE range, which are conditions that are unhealthy for sensitive groups. Ozone levels will climb into the moderate range but should be limited to that with the haze from the smoke present.


*** Extended Outlook: A weak cold front will improve air quality conditions on Wednesday to bring concentrations of fine particulate matter back into the moderate range. Ozone levels will be limited to the good range with a chance for showers early before a mix of sun and clouds by the afternoon. Highs will be in the mid-80s for the second half of the week. --- Roble

Here are some Air Quality Action Day tips you can follow to help reduce pollution:

Days when ozone concentrations are expected to be high:

• Conserving electricity by setting air conditioning to a higher temperature;
• Combining errands to reduce vehicle trips;
• Limiting engine idling; and
• Refueling cars and trucks after dusk.

Days when particle pollution levels are expected to be high:

* Reduce or eliminate fireplace and wood stove use.
* Avoid using gas-powered lawn and garden equipment.
* Avoid burning leaves, trash and other materials.


For more information, visit DEP at, EPA’s AirNow at, or Delaware Valley Regional Planning Commission’s Air Quality Partnership at


To follow air quality in PHL between forecasts: "aqforecast" at