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Castle Rock, CO Air Quality

← Castle Rock

Air quality in Castle Rock

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
45
Good
PM2.5
10.9 µg/m³
WHO guideline 15
PM10
11.6 µg/m³
WHO guideline 45
NO₂ · O₃
16 · 50
µg/m³

Hour by hour (12h)

US EPA AQI
10:00 PM 💨 PM2.5 10.9 µg/m³
45Good
11:00 PM 💨 PM2.5 10.7 µg/m³
45Good
12:00 AM 💨 PM2.5 10.5 µg/m³
44Good
1:00 AM 💨 PM2.5 10 µg/m³
42Good
2:00 AM 💨 PM2.5 9.3 µg/m³
39Good
3:00 AM 💨 PM2.5 8.4 µg/m³
35Good
4:00 AM 💨 PM2.5 7.7 µg/m³
32Good
5:00 AM 💨 PM2.5 6.9 µg/m³
29Good
6:00 AM 💨 PM2.5 6.4 µg/m³
27Good
7:00 AM 💨 PM2.5 5.8 µg/m³
24Good
8:00 AM 💨 PM2.5 4.9 µg/m³
23Good
9:00 AM 💨 PM2.5 5 µg/m³
27Good

Next few days

daily max · US EPA AQI
Wed 💨 Moderate · UV Very high
83
Thu 💨 Moderate · UV Very high
73
Fri 💨 Moderate · UV High
51
Sat 💨 Good · UV High
50
Sun 💨 Moderate · UV High
55
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Updated: 10:41 PM