NEW YORK (PIX11) — Officials in New York and New Jersey urged residents to stay indoors as much as possible Thursday as another day of dangerous and unhealthy air quality was expected across the region due to wildfire smoke from Canada.

An Air Quality Alert remains in effect across the tri-state area at least through the end of the day Thursday. Officials warned it could be extended to Friday.

On Wednesday evening, the Air Quality Index in New York City hit 484. The index tops out at 500. New York City was ranked No. 1 in the world for worst air quality.

Officials warned that while air quality may improve at times, the levels are still hazardous, particularly for people with asthma, heart and lung disease, or general breathing problems, the air quality could cause short-term health issues. Children and adults over 65 are also vulnerable.

Below you will find the most up-to-date information on air quality and wildfire smoke impacting New York and New Jersey. This is a developing story. Refresh this page for updates.