Today's Forecast Map

AQI Forecast Maps:

Hover over each region for the AQI forecast

Today's Air Quality Forecast

Map Courtesy of Air Quality Ontario

Local Hourly Air Quality Report

Health Effects:
Very good Good Moderate Poor Very poor
1 - 15 16 - 31 32 - 49 50 - 99 100+

The Air Quality Index (AQI) is an indicator of air quality, based on hourly pollutant measurements of some or all of the six most common air pollutants: sulphur dioxide, ozone, nitrogen dioxide, total reduced sulphur compounds, carbon monoxide and fine particulate matter.

Here's what the readings mean:
  • If the air quality value is below 32, the air quality is considered relatively good.
  • If the AQI value is in the range of 32 to 49 (moderate category), there may be some adverse effects on very sensitive people.
  • An index value in the 50 to 99 range (poor category), may have some short-term adverse effects on the human or animal populations, or may cause significant damage to vegetation and property.
  • An AQI value of 100 or more (very poor category) may cause adverse effects on a large proportion of those exposed.

Queen's Printer for Ontario, 2010