Air quality over the US and Canada is slowly getting better. But the threat of more wildfires sending smoke across the border looms
Photos show New York haze caused by Canada wildfire smoke
Smoke Pouring From Wildfires Snarls Air Travel in and Out of NYC
Western wildfire smoke causes cross-country air pollution
NYC in code red 'unhealthy' air quality as Canadian wildfire smoke pours into Northeast
The US and Canada saw dangerous smoke this week. It's a routine peril for many developing countries
Unhealthy' Smoke From Canada's Fires Streams Into Northeast
Tens of millions under air quality alerts in US as Canada fire smoke drifts south, Pollution
Before-and-After Pictures Show How Smoke Has Engulfed New York
Photos show New York haze caused by Canada wildfire smoke
Wildfire Smoke: Smoke From Canada Fires Stretches From Midwest to East Coast - The New York Times
Air quality concerns continue into Thursday as wildfire smoke covers Northeast
Toronto, New York and Washington blanketed by smoke from Canadian wildfires - ABC News
Photos: Canada wildfire smoke shrouds iconic American landmarks
8) What Canada's unprecedented wildfire season could mean for the US