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Weather in San Marcos, California

02:05 AM
Now
Cloudy Night
48° F
Feels Like 46°
Precipitation 0 %
Wind 5 mph
Humidity 45 %
Today
Cloudy Weather
Day 72°
Night 37°
Precipitation 0 %
Wind 6 mph
UV Index (0 - 11+) 3

San Marcos Weather Forecast Updated

Last updated on

Air Quality in San Marcos

NOW
56 AQI
Moderate air quality Dominant pollutant: PM2.5

Pollutant Concentrations:

PM2.5 14.86 µg/m³
PM10 24.96 µg/m³
O3 0.053 ppm
NO2 1.4 ppb
SO2 0.6 ppb
CO 0.17 ppm
NH3 0.42 µg/m³
NO 0 µg/m³
PM2.5 – Fine particles <2.5μm
PM10 – Inhalable particles <10μm
O3 – Ozone
NO2 – Nitrogen dioxide
SO2 – Sulfur dioxide
CO – Carbon monoxide
NH3 – Ammonia
NO – Nitric oxide

Health Recommendations:

Air quality is acceptable; however, for some pollutants, there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.

Show raw pollutant concentrations (µg/m³)
PM2.514.86 µg/m³
PM1024.96 µg/m³
O3104.65 µg/m³
NO22.56 µg/m³
SO21.52 µg/m³
CO194.67 µg/m³
NH30.42 µg/m³
NO0 µg/m³