SEATTLE — People in western Washington woke up to hazy skies the morning after Fourth of July, and the Seattle area's air quality was among the worst of major U.S. cities Friday, according to IQ Air.
The diminished air quality came as western Washington was set to be under a heat advisory beginning Friday afternoon, with temperatures expected to reach the upper 80s and even 90 degrees in some areas.
As of 6:45 a.m. Friday, Seattle ranked as the third-worst air quality of any major U.S. city, behind only Detroit and Los Angeles.
The poor air quality was due to lingering smoke from fireworks on the Fourth of July, according to KING 5 Senior Meteorologist Rich Marriott.
Marriott said the air was most unhealthy around 1 a.m. Friday in most areas, which was due to all the smoke from the fireworks going off. He said that the smoke accumulated near the ground due to warmer air above, and colder air at the surface.
"That forms an inversion, which is like putting the lid on a pot. It keeps everything that goes into the air near the ground there," said Marriott. "So all the fireworks went off last night sitting underneath there, so it's all concentrated into a few hundred feet right by the ground, and so you get terrible air quality all of a sudden out of nowhere."
While the overall AQI of 92 is "moderate" per IQ Air's system, many reporting stations in the area were reporting AQIs well into the 100s. In particular, the Queen Anne area, Rainier Valley and the Madrona/Leschi neighborhoods were seeing the highest figures.
“You could definitely tell people were setting off explosions last night,” said Allison Peters, who was spending Friday at Alki Beach in Seattle. “When I walked outside, I could smell it, like you could smell the remnants of the fireworks.”
“Yesterday we had driven around this area and saw Mt. Rainier really clearly, but I don't feel like it was there today,” said Elizabeth Dawson, who was also spending time at Alki Beach.
Outside of Seattle, many of Kirkland's stations were reporting an AQI over 150, while Bothell was seeing AQI just shy of 200. For reference, anything between 151-200 is considered "unhealthy" for all people, not just those groups that might be more sensitive to worse air quality.
Better air quality could be seen on the map west and east of the Puget Sound. Stations in Issaquah and Snoqualmie are reporting good air quality on Friday morning, while parts of Bainbridge Island and area west of Bremerton are also seeing a low AQI index.
By Friday afternoon, air quality had improved for most parts of western Washington with good or moderate air quality reported across the region.
Despite the air quality, no burn bans are currently in effect, per the Puget Sound Clean Air Agency. There are several wildfires burning in central Washington, with smoke being visible from space.
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