Conditions are slowly starting to improve, smoke-wise, and tomorrow should be a bit better than today, with the air quality alert being “orange” (unhealthy for sensitive groups) vs. today’s red (unhealthy for all) to purple (very unhealthy for all) and even hazardous in NYC and parts of NJ, depending on where one was. In fact, NYC's air quality index hit its highest level since the AQI was established in 1999 (377 - considered hazardous).
https://www.foxweather.com/weather-news/new-york-nyc-air-quality-levels-canadian-wildfire-smoke
See the graphic below for the AQI across our region as of 10 pm tonight and see the link below for the website that hosts this graphic and has tools for looking back at recent AQI levels and forward, based on modeling predictions for the next day. Tomorrow, winds will start to shift more towards the west, as the vertically stacked low to our NE retrogrades into New England, shifting the worst of the smoke westward and Friday’s air quality will be even better due to a further wind shift, combined with likely showers.
https://gispub.epa.gov/airnow/?show...orecastmonitors=forecasttomorrow&tab=forecast
Note that the high AQI levels are largely due to the PM2.5 levels, i.e., particulates < 2.5 microns, resulting from incomplete combustion of wood/cellulouse from the fires in Quebec. Prior to the passage of the Clean Air Act in 1970, many US cities had episodes of particulate pollution, from poorly controlled burning of fossil fuels in power plants, cars, incinerators, etc., similar to what we're seeing from these fires. Horrible smog (smoke/fog) outbreaks in the years prior to 1970 in many major US cities, including NYC (usually from a meteorological inversion trapping pollutants locally) were a major impetus for passage of the Clean Air Act, which has been a huge success for air quality and public health.