Canadian wildfires have created dangerous air quality conditions in New York City.

The New York Department of Environmental Conservation issued an air quality health advisory Tuesday for New York, Bronx, Kings, Queens and Richmond counties as well as surrounding suburbs. The state’s Department of Health recommends that “individuals consider limiting strenuous outdoor physical activity to reduce the risk of adverse health effects.”

Young people and those with respiratory problems will be particularly impacted.

Fires in Quebec and Nova Scotia are being blamed for the haze that’s crept across parts of New York City. The Canadian Broadcasting Corporation said Sunday firefighters in Quebec were unable to contain more than 150 fires tearing through the province. Firefighter and military personnel throughout Canada traveled to provide assistance. French President Emmanuel Macron committed 100 firefighters to assist the Québecois, with whom France shares cultural and historic ties.

The National Weather Service calls for widespread haze and patchy smoke over New York City on Tuesday night. Air quality could be affected throughout the week. According to Weather.com, smoke passing through the northeast Tuesday was traveling closer to the ground than in recent weeks, making it more dangerous. A low pressure system on the New England coast reportedly pushed smoke southward and into the New York area Monday, leading to Tuesday’s “unhealthy” conditions. CNN said Monday that smoke lingering over the city at high altitudes was keeping temperatures down and creating a visible haze.

More than 8 million acres of Canadian land has burned in 2023. Quebec has seen at least a half-million acres consumed by wildfires already.

The National Weather Service issued “Red Flag Warnings” for New Jersey, Pennsylvania, Michigan, Washington and Alaska, where dry and unstable conditions raise the possibility for wildfires. Outdoor burning is discouraged until those warnings pass, which is expected to come after 8 p.m. local time.