Smoke and haze filled the skies across the Northeast on Tuesday, as wildfires burning hundreds of miles away in Canada made the air unhealthy in New York City, Boston and elsewhere. …The forecast computer model in the map above shows where the thickest smoke is likely near the surface over the next several hours. Many of the fires burning in Quebec started days ago, if not weeks. But a storm system swirling off the coast of Nova Scotia forced the smoke from these fires south into the United States, and then east. The weather pattern pushing smoke to the Northeast is expected to persist for the next several days, with haze likely to continue across the region. So far this year, 600 square miles have burned throughout Quebec, according to NASA. In a typical year, barely a square mile would have burned, according to the province’s fire prevention agency. Fire season in Quebec and Canada usually starts in May, slightly before the typical start of fire activity in the United States. So far there have been few major U.S. fire outbreaks.