The smell of smoke filled the air in New York City Monday morning. Its source was a 1,600-acre brush fire in Wharton State Forest, NJ – about 90 miles away.
Burning since late Sunday, the smoke was trapped near the ground by a local temperature inversion. This is a weather phenomenon where the temperature in the atmosphere increases with height instead of decreasing. Essentially, the inversion layer acted like a lid and caused the smoke to spread out horizontally rather than vertically. A low level wind from the southeast then carried the smoke toward the city.
The smoky haze prompted the EPA to issue an air quality alert for the NYC area. With a spike in the pollutant known as “fine particulate matter”, this was the first time this year that the city’s air quality dropped below “moderate” on the agency’s AQI scale.