Worst air pollution San Luis Obispo, today and tomorrow
Today (15 July): Air quality in San Luis Obispo is fair. PM2.5 and PM10 are fair; AQI, NO2, and O3 are medium; SO2, CO, HCHO, and PM1 are good. Pollution peaks around 3:00 PM (NO2: 51.4/100).
Tomorrow (16 July 2026): Air quality in San Luis Obispo is fair. SO2 increases to fair; PM1 increases to fair; all other pollutants stay as today. Pollution peaks around 6:00 PM (NO2: 57.2/100). 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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San Luis Obispo's air quality is shaped largely by Central Coast marine air; afternoon sea breeze generally keeps conditions favorable. Overall, San Luis Obispo sees air quality that tracks fairly closely with typical conditions for its wider region. Visitors and residents alike tend to notice the clearest air outside the warmest summer weeks.
Today - 15 July | Pollution peaks at 15:00
AQI:
Medium
51.4/100
PM2.5 (fine particles):
Fair
31.7/100
PM10 (coarse particles):
Fair
38.9/100
NO2 (nitrogen dioxide):
Medium
51.4/100
O3 (ozone):
Medium
42.7/100
SO2 (sulfur dioxide):
Good
15.4/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
4.5/100
PM1 (ultrafine particles):
Good
17.1/100
Levels show the poorest local air quality during the day
Tomorrow - 16 July | Pollution peaks at 18:00
AQI:
Medium
57.2/100
PM2.5 (fine particles):
Fair
32.8/100
PM10 (coarse particles):
Fair
33.8/100
NO2 (nitrogen dioxide):
Medium
57.2/100
O3 (ozone):
Medium
41.4/100
SO2 (sulfur dioxide):
Fair
21.4/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
5.2/100
PM1 (ultrafine particles):
Fair
27.6/100
Pollen forecast in San Luis Obispo
View pollen forecastFrequently Asked Questions
Is air quality bad in San Luis Obispo right now?
On 15 July 2026, overall air quality in San Luis Obispo is fair. PM10 is the main pollutant at 38.9/100. Pollution peaks around 3:00 PM (NO2: 51.4/100).
Will air quality be worse tomorrow in San Luis Obispo?
On 16 July 2026, air quality conditions in San Luis Obispo will be similar to today, with PM10 forecast at fair at 33.8/100. Pollution peaks around 6:00 PM (NO2: 57.2/100).
When is air pollution at its worst in San Luis Obispo?
San Luis Obispo's air quality has a clear seasonal rhythm — the shortest stretch of clean air usually falls in the wetter winter months, whereas from August into October, wildfire smoke can add sharp particulate spikes on top of the usual summer ozone. Coastal breezes offer some relief compared to inland valley locations that see heavier smog buildup.
Are air quality levels in San Luis Obispo 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.
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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