Wildfire smoke blankets Northeast, triggers hazardous air quality alerts.

Smoke from Canadian wildfires has caused unhealthy air quality in major metro areas including New York, Boston, Philadelphia, and Washington, D.C. The National Weather Service has issued air quality advisories for all groups, and the New York State Department of Environmental Conservation has issued an air quality health advisory through Thursday. The situation is considered a health and environmental crisis, and New York's state government has announced a plan to distribute 1 million free N95 masks.