Another air quality alert is in effect Tuesday for NYC, western Long Island, the Hudson Valley, northwest New Jersey and southwest Connecticut.

Canadian wildfires are the cause of an air quality alert that’s in effect for the tri-state area, according to health officials. New York City’s air quality index is at 118 on Tuesday, AirNow’s tracker indicates.

The New York State Department of Environmental Conservation issued the alert due to elevated levels of fine particulate matter in the air. Air Quality Index (AQI) values are forecasted to rise above 100, indicating unhealthy conditions for sensitive groups, including children, the elderly, and individuals with respiratory or heart conditions.