San Marcos, Texas, United States Historical Air Quality Analysis
Dive into detailed Air Quality Insights with historical data, monthly patterns, and yearly trends at your fingertips!
August Air Quality Analysis
San Marcos, Texas, United States
AQI Trends: Highest and Lowest
Same Day Analysis (8th August ):
On this day, AQI across the 1 years varied significantly: 2025 ranks 1st highest AQI at 35 of Good air quality on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 8th Aug - 9th Aug 2025
San Marcos, Texas, United States
6 AM8th Aug 2025
8 PM
5 AM9th Aug 2025
44AQI
34AQI
40AQI
28AQI
In the last 24 hours,
San Marcos's AQI reached its highest point of 44 at 12 PM during the Day, while the lowest point, 28, was recorded at 5 AM during the Night between 8th Aug and 9th Aug 2025.
Day & Night AQI Trend : Jul - Aug 2025
San Marcos, Texas, United States
28°C22/37°C
28°C23/34°C
29°C25/35°C
28°C24/33°C
28°C24/34°C
30°C22/38°C
30°C23/39°C
30°C22/39°C
29°C22/38°C
31°C23/39°C
28°C25/32°C
30°C24/36°C
30°C22/39°C
31°C24/39°C
31°C22/40°C
29°C23/36°C
28°C23/36°C
29°C25/35°C
30°C23/39°C
30°C23/40°C
31°C20/41°C
31°C21/41°C
32°C24/41°C
30°C24/41°C
31°C23/39°C
30°C25/37°C
31°C22/39°C
31°C23/39°C
32°C25/40°C
31°C23/40°C
--°C/°C
44AQI
37AQI
40AQI
38AQI
2025 Days Vs Air Quality
San Marcos, Texas, United States
71%
96
29%
40
Total number of days with different AQI categories in last 221 days in 2025 (144 days remaining)
Under WHO’s Safe Air Quality Limits: 71%
Health Risk Level:
Low
In 2025, 71% of 221 days were within WHO’s safe air quality limits. The risk of health issues is Low, but the long-term effects, especially on vulnerable individuals, remain uncertain.
Annual Air Quality Insights
San Marcos, Texas, United States
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
30AQI
26AQI
26AQI
42AQI
68AQI
59AQI
54AQI
64AQI
71AQI
61AQI
30AQI
20AQI
22AQI
31AQI
36AQI
40AQI
42AQI
50AQI
40AQI
42AQI
46AQI
46AQI
40AQI
54AQI
62AQI
38AQI
26AQI
43AQI
41AQI
55AQI
50AQI
58AQI
48AQI
51AQI
45AQI
53AQI
57AQI
43AQI
28AQI
28AQI
33AQI
47AQI
40AQI
42AQI
26AQI
33AQI
37AQI
33AQI
39AQI
47AQI
61AQI
66AQI
69AQI
56AQI
62AQI
67AQI
54AQI
58AQI
48AQI
54AQI
58AQI
58AQI
34AQI
33AQI
34AQI
36AQI
43AQI
47AQI
50AQI
58AQI
54AQI
50AQI
54AQI
60AQI
57AQI
48AQI
43AQI
32AQI
26AQI
42AQI
54AQI
49AQI
32AQI
37AQI
56AQI
53AQI
50AQI
32AQI
37AQI
44AQI
29AQI
23AQI
26AQI
22AQI
22AQI
23AQI
45AQI
46AQI
53AQI
40AQI
47AQI
61AQI
60AQI
54AQI
45AQI
33AQI
42AQI
47AQI
38AQI
30AQI
33AQI
49AQI
60AQI
62AQI
47AQI
44AQI
42AQI
48AQI
39AQI
34AQI
27AQI
27AQI
30AQI
36AQI
44AQI
58AQI
54AQI
48AQI
32AQI
31AQI
34AQI
30AQI
33AQI
35AQI
35AQI
35AQI
42AQI
45AQI
46AQI
42AQI
44AQI
33AQI
No. of days
202544AQI
Highest AQI recorded in
May46AQI
Lowest AQI recorded in
August33AQI
Most & Least Polluted Years Over the Last 1 Years
San Marcos's annual 2025 AQI (44) shows an average percentage change of NaN% (improved AQI) compared to previous years: .