Air quality has taken a serious hit across the United States as a twofold blow of wildfires in the West and in Canada have sent smoke pouring across large sections of the country — a problem that’s set to linger for days.

Air quality alerts are in effect in the Philadelphia area, fueled by smoke from wildfires that are burning thousands of miles away.

Each New England state has seen an uptick in the number of days over the last five years when fine particulate matter (PM2.5) or ozone exceeds air quality standards that are considered “unhealthy for sensitive groups.