Air Quality Advisory Days have been declared in the Youngstown-Warren region from Sunday through Monday, July 17 according to the Eastgate Regional Council of Governments.

An approaching cold front will push dense smoke from Canadian wildfires into the Mahoning Valley. The conditions will increase particle levels between Sunday afternoon and Monday afternoon. In addition, a temperature inversion Monday morning will trap smoke near the surface.

As a result, the Air Quality Index will be Unhealthy for Sensitive Groups on Sunday and Unhealthy on Monday.

When air quality is in the Unhealthy for Sensitive Groups range, people who are in sensitive groups, whether the increased risk is due to medical conditions, exposure conditions, or innate susceptibility, may experience health effects when engaged in outdoor activities. However, exposures to ambient concentrations in this range are not likely to result in effects on the general population. For particle pollution, the sensitive groups include people with heart and lung disease, older adults, children, people with diabetes, and people of lower socio-economic status.

When air quality is Unhealthy, everyone who is active outdoors may experience effects. Members of sensitive groups are likely to experience more serious effects.

Tuesday, as the front departs northeastern Ohio, winds will shift from northerly to northwesterly, aiding the dispersion of smoke. However, pollutant carryover from the previous days will yield high-Moderate AQI levels.

Wednesday, calm to light winds will hinder dispersion, allowing light smoke to linger in the Mahoning Valley. Additionally, periods of sunshine will promote ozone formation.

Because of those conditions, AQI levels will be mid-Moderate.

On Thursday, as the next cold front moves across Ohio, mixing will increase. However, light westerly to southwesterly winds will limit dispersion, and warm temperatures will support ozone development. These conditions will yield low-Moderate AQI levels.

Friday, west-northwesterly winds behind the front will transport smoke into Youngstown-Warren, increasing particle levels. As a result, AQI levels will be mid-Moderate.