The map shows the distribution of smoke from wildfires in the United States and Canada.
Maine and some other New England states are being visited by smoke from fires in Canada. Here is how NOAA describes it:
New England and Eastern Canada:
Very large fires across the Boreal Quebec (particularly, south of La Grande Riviere Reservior) have produced very dense smoke that has migrated E and SE over the last day and covers the Western portions of the St. Lawrence Seaway into New Brunswick and far E ME. Thin smoke surrounds out to Nova Scotia but also extending SE along and over SE New England into the Hudson Valley Shelf/Canyon region off NJ/NY and about 50km offshore of the Delmarva.
