The east coast of the U.S. woke up today to a surreal state of thick yellow haze that has disrupted the lives of tens of millions.

The National Weather Service has issued a warning to Americans in light of the expected difficulties for some of them to breathe. The fires are currently mostly in the provinces of Quebec, Nova Scotia and Ontario in Canada, and winds have led to the cloud screen covering entire parts of its southern neighbor. So far, some 30 million hectares have burned across Canada, including in the west of British Columbia.