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Weekly Weather Event -Week of July 19th

July 24, 2021

Earlier this week, wildfire smoke from the western United States and Canada caused more than just hazy skies. As the smoke traveled east, it brought poor air quality to areas far from the source of the fires. Large population centers such as Philadelphia, New York City, and Washington D.C. issued air quality advisories, warning at-risk groups to limit time outside. Similar warnings were issued throughout the Midwest.

The Air Quality Index (AQI) was developed by the Environmental Protection Agency (EPA) as a way to measure how air pollution impacts human health. During this recent air pollution episode, New York City had an AQI reading of 130 on the evening of July 20th. An AQI reading between 101 and 150 indicates that pollution levels are high enough to cause health problems in sensitive groups, such as people with asthma, older adults, and young children.

Wildfires primarily produce particulate pollution, or small solid or liquid droplets. These particulates can get into the lungs and cause health problem as they enter the body. When particulate pollution is high, air filters can help remove pollution from indoor air. When outside, you can protect your lungs by wearing a face mask.