Much of the United States is under an ominous, hazy sky on Tuesday as smoke spreads from the massive wildfires in the West.
At least 40 million Americans are experiencing poor air quality.
These New York City photos show the difference between Tuesday and a typical sunny day.
At least 80 large wildfires are burning in 13 states, mostly in the West.
Oregon's Bootleg Fire has exploded to over 388,000 acres and is 30% contained as of Tuesday morning.
"Fighting this fire is a marathon, not a sprint," said Rob Allen, incident commander for PNW Incident Management Team 2.
The Dixie Fire in Butte County, California, has spread to over 59,000 acres and is just 15% contained.
The danger for wildfires will remain high on Tuesday due to low humidity, high wind gusts and the potential of dry lightning.
Fire danger will continue Wednesday before subsiding some on Thursday. But with the West enduring a widespread drought, new fires could easily spread at any time.