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San Marcos, CA Air Quality

← San Marcos

Air quality in San Marcos

The US Air Quality Index (EPA) grades air from 0 to 500 using fine particles (PM2.5/PM10), ozone and nitrogen dioxide. 0-50 is Good, 51-100 Moderate, 101-150 Unhealthy for Sensitive Groups, and anything higher affects everyone.

US AQI · EPA
57
Moderate
PM2.5
14.8 µg/m³
WHO guideline 15
PM10
19 µg/m³
WHO guideline 45
NO₂ · O₃
17 · 60
µg/m³

Hour by hour (12h)

US EPA AQI
10:00 PM 💨 PM2.5 14.8 µg/m³
57Moderate
11:00 PM 💨 PM2.5 16.2 µg/m³
60Moderate
12:00 AM 💨 PM2.5 17.7 µg/m³
63Moderate
1:00 AM 💨 PM2.5 18.6 µg/m³
65Moderate
2:00 AM 💨 PM2.5 19.2 µg/m³
66Moderate
3:00 AM 💨 PM2.5 19.4 µg/m³
66Moderate
4:00 AM 💨 PM2.5 19.1 µg/m³
66Moderate
5:00 AM 💨 PM2.5 17.6 µg/m³
63Moderate
6:00 AM 💨 PM2.5 16 µg/m³
59Moderate
7:00 AM 💨 PM2.5 14.9 µg/m³
57Moderate
8:00 AM 💨 PM2.5 14.9 µg/m³
57Moderate
9:00 AM 💨 PM2.5 15.4 µg/m³
58Moderate

Next few days

daily max · US EPA AQI
Tue 💨 Moderate · UV Very high
61
Wed 💨 Moderate · UV Very high
83
Thu 💨 Moderate · UV Very high
86
Fri 💨 Moderate · UV Very high
72
Sat 💨 Moderate · UV Very high
85
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Updated: 10:16 PM