Worst air pollution Fremont - Seattle, today and tomorrow
Today (15 July): Air quality in Fremont is fair. NO2 is fair; AQI and O3 are medium; PM2.5, PM10, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 7:00 AM (O3: 52.9/100).
Tomorrow (16 July 2026): Air quality in Fremont is medium. NO2 decreases to good; all other pollutants stay as today. Pollution peaks around 4:00 AM (O3: 51.8/100). Airmine updates local air quality forecasts four times daily.
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Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team
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Seattle's Fremont records moderate Seattle air quality, shaped by traffic on Aurora Avenue and the Ship Canal bridges and its low-lying position relative to Queen Anne and Capitol Hill above. The Lake Union waterfront a short distance east provides periodic ventilation, with prevailing southwesterly winds keeping conditions acceptable.
Today - 15 July | Pollution peaks at 07:00
AQI:
Medium
52.9/100
PM2.5 (fine particles):
Good
13.0/100
PM10 (coarse particles):
Good
4.7/100
NO2 (nitrogen dioxide):
Fair
24.8/100
O3 (ozone):
Medium
52.9/100
SO2 (sulfur dioxide):
Good
1.1/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
7.5/100
PM1 (ultrafine particles):
Good
16.0/100
Levels show the poorest local air quality during the day
Tomorrow - 16 July | Pollution peaks at 04:00
AQI:
Medium
51.8/100
PM2.5 (fine particles):
Good
11.1/100
PM10 (coarse particles):
Good
3.8/100
NO2 (nitrogen dioxide):
Good
18.6/100
O3 (ozone):
Medium
51.8/100
SO2 (sulfur dioxide):
Good
1.0/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
11.5/100
PM1 (ultrafine particles):
Good
13.5/100
Other Landmarks in Seattle
Sports venues in Seattle
Frequently Asked Questions
Is air quality bad in Fremont right now?
On 15 July 2026, overall air quality in Fremont is fair. NO2 is the main pollutant at 24.8/100. Pollution peaks around 7:00 AM (O3: 52.9/100).
Will air quality be worse tomorrow in Fremont?
On 16 July 2026, air quality conditions in Fremont will be better than today, with AQI forecast at medium at 51.8/100. Pollution peaks around 4:00 AM (O3: 51.8/100).
When is air pollution at its worst in Fremont?
Fremont's air quality follows a clear seasonal pattern — rain-heavy winters keep the air unusually clean compared to much of the country, whereas by late summer, wildfire smoke can override the region's usual clean-air advantage for days at a time. Prevailing onshore winds usually keep pollution moving rather than letting it settle.
Are air quality levels in Fremont based on measurements or forecasts?
It is forecasts derived by downscaling forecasts provided by EU’s Copernicus Atmosphere Monitoring Service (CAMS) by taking into account local conditions such as traffic patterns. CAMS bases its forecast on satellite measurements of particles and chemical compounds in the atmosphere. Airmine’s services were developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team.
Want to see air quality forecasts for other cities in United States?
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Data provided by Airmine — Last update: 16 July 2026 at 10:33 CEST (Data is updated four times daily.)
This forecast is produced independently using Airmine's own atmospheric data and models.
Unless explicitly made clear, the content on this site has not been paid for by external organisations and is Airmine's sole responsibility.
For long term forecasts and maps, see the Airmine app