Worst air pollution San Marcos HS's Baseball Diamond - San Marcos, today and tomorrow
Today (9 August): Air quality in San Marcos HS's Baseball Diamond is fair. AQI, PM10, and O3 are fair; PM2.5, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 4:00 AM (O3: 23.2/100).
Tomorrow (10 August 2026): Air quality in San Marcos HS's Baseball Diamond is fair. PM10 decreases to good; all other pollutants stay as today. Pollution peaks around 9:00 AM (O3: 21.0/100). Airmine updates local air quality forecasts four times daily.
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San Marcos HS's Baseball Diamond in San Marcos sits on the flat San Diego County inland valley at the San Luis Rey River corridor, with vehicle traffic and the surrounding suburban residential corridor contributing local sources. Consistent Pacific sea breezes provide maritime ventilation and the diamond generally maintains moderate to good conditions throughout most of the year.
Today - 9 August | Pollution peaks at 04:00
AQI:
Fair
23.2/100
PM2.5 (fine particles):
Good
16.3/100
PM10 (coarse particles):
Fair
21.6/100
NO2 (nitrogen dioxide):
Good
3.0/100
O3 (ozone):
Fair
23.2/100
SO2 (sulfur dioxide):
Good
2.2/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
1.1/100
PM1 (ultrafine particles):
Good
5.9/100
Levels show the poorest local air quality during the day
Tomorrow - 10 August | Pollution peaks at 09:00
AQI:
Fair
21.0/100
PM2.5 (fine particles):
Good
15.5/100
PM10 (coarse particles):
Good
16.3/100
NO2 (nitrogen dioxide):
Good
8.2/100
O3 (ozone):
Fair
21.0/100
SO2 (sulfur dioxide):
Good
2.3/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
1.4/100
PM1 (ultrafine particles):
Good
6.1/100
Sports venues in San Marcos
Frequently Asked Questions
Is air quality bad in San Marcos HS's Baseball Diamond right now?
On 9 August 2026, overall air quality in San Marcos HS's Baseball Diamond is fair. AQI is the main air quality indicator at 23.2/100. Pollution peaks around 4:00 AM (O3: 23.2/100).
Will air quality be worse tomorrow in San Marcos HS's Baseball Diamond?
On 10 August 2026, air quality conditions in San Marcos HS's Baseball Diamond will be similar to today, with AQI forecast at fair at 21.0/100. Pollution peaks around 9:00 AM (O3: 21.0/100).
When is air pollution at its worst in San Marcos HS's Baseball Diamond?
At San Marcos HS's Baseball Diamond, air quality tends to follow San Marcos's broader seasonal rhythm — winter rains provide the only real relief from an otherwise persistent haze, whereas summer and early autumn bring the highest ozone levels, and wildfire smoke can spike particulate readings sharply from August through October. The mountains ringing the basin can trap pollution close to the ground for days when winds are calm.
Are air quality levels in San Marcos HS's Baseball Diamond 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.
Why doesn’t the forecast always reflect wildfire impacts?
Airmine’s forecast uses CAMS (Copernicus Atmosphere Monitoring Service) as its background atmospheric model. While CAMS includes wildfire emissions, these are derived from satellite observations and are not available in real time. During rapidly evolving wildfire events, there may therefore be a delay before increased emissions are incorporated into the model. As a result, the forecast may temporarily underestimate PM₂.₅ and other pollutants associated with wildfire smoke.
During rapidly evolving wildfire events, CAMS may lag by approximately 1–2 days before increased wildfire emissions are fully represented, which can lead to temporary underestimation of PM₂.₅ concentrations in Airmine’s forecast.
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Data provided by Airmine — Last update: 10 August 2026 at 02:34 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.
Disclaimer: Forecasts are provided for informational purposes only and should not be relied upon as medical advice. Actual pollen and air quality conditions may vary from the forecast. If you have allergies, asthma, or another medical condition, consult a healthcare professional. Please see our Terms of Service for important information about limitations of liability.
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